Infantry Discussion Thread 6: True Korea Edition

[Vancon]

Relevant Pagetop Edit

You have to change the colour you're using ever so slightly to a slightly darker shade, and then rinse wash repeat until preferred.Kinda like how I did the tops of my ships here, but darker colours instead of brighter ones.

Speaking of light, time to repost my stormtroopers again!
(Image)
*beats the dead horse*


Cheers mate.

If I remember stormtrooper can been penetrated anywhere with a sharpened stick and is inappropriately defective against massed slingers.

They're still cool as fuck yo.

[The Archangel Conglomerate]

I wanted to avoid the "dark grey pistol with a dark grey grip" theme with the Tauxie, so I tried a cream grip, but it just looks like shit.
I don't really know what to do with it now. Halp pls.

First off, I'd suggest a lighter palette. That should actually help immensely. Then I'd suggest adding some grey around the ivory, giving it a bit of a panel look.

---

Many are likely outdated

I remember being legit upset that I wasn't on this. Then Trans showed up and told us to quit bitching. Then I felt like a twat for being upset over not being on some list.

[Anshaskia]

I wanted to avoid the "dark grey pistol with a dark grey grip" theme with the Tauxie, so I tried a cream grip, but it just looks like shit.
I don't really know what to do with it now. Halp pls.

What are those three square things on the slide?

[Crookfur]

I wanted to avoid the "dark grey pistol with a dark grey grip" theme with the Tauxie, so I tried a cream grip, but it just looks like shit.
I don't really know what to do with it now. Halp pls.

What are those three square things on the slide?

Scifi space grebles for gaussy raily stuff

[New Visegrad]

I wanted to avoid the "dark grey pistol with a dark grey grip" theme with the Tauxie, so I tried a cream grip, but it just looks like shit.
I don't really know what to do with it now. Halp pls.

First off, I'd suggest a lighter palette. That should actually help immensely. Then I'd suggest adding some grey around the ivory, giving it a bit of a panel look.

But muh tactical grey

It's not supposed to be a panel :\ it's a one-piece grip made out of futurplastic or whatever. It's roundish.

I wanted to avoid the "dark grey pistol with a dark grey grip" theme with the Tauxie, so I tried a cream grip, but it just looks like shit.
I don't really know what to do with it now. Halp pls.

What are those three square things on the slide?

Gauss coil housings. They're not really on the side, they wrap around over the top of the barrel.

[Doppio Giudici]

What rifle am I most likely to find in the hands of penal companies that fire upon my military?

[Puzikas]

As many of you know, there are three main stages of ballistics. Internal, or the phase of the projectile within the firearm, External, the phase of the projectile in flight, and Terminal, the final phase of the projectiles flight path, as it strikes (and travels through) the target.

As some of you may not know, I study ballistics. I do so as a maner of hobby and a matter of career; as a civilian shooter, I take interest in internal and external ballistics for long range shooting. As a matter of employment, I study terminal ballistics and trauma.

So what does that mean? Well, quite simply, as a matter of study I deal mostly with traumatic wounds; be these gunshots, stabs, cuts, or blunt force trauma, this is my primary field of study and practice. I am particularly interested in gunshot wounds and their actions therein. I have taken an interest in these during my military career, furthering my knowledge in the post-military years at the collegiate level while employed in law enforcement, and currently am employed in the field.

To put it quite simply: I study how you die.

My knowledge of said actions and study is well known within the guard of the thread, I would think, having broken down many wounding methods and explaining how they work. I think now would be a good time, then, to condense the information to one post, one catch all to help you better understand how it is that bullets wound, what wounding effects are, how the construction of bullets affect their wound profiles, and wound profiles as a whole.

So, let's start.

In terminal performance, various factors contribute to an actual wound profile of a bullet. These terms shall be defined and explained for your understanding.

Velocity is a measure of the projectiles speed, normally measured in feet or meters per second.

Caliber is a measure of the projectiles diameter, normally given in inches or millimeters. It is also used to define cartridges, the name proper of the packaging of the projectile(s) consisting of case, powder, primer, and projectile. It may also be used to define the length of a projectile; A bullet that is 6mm in diameter and is 5 calibers long is 30mm.

Weight or mass is a seldom used term in it of itself. Normally however ma's is used to refer to a projectiles weight. It is normally given in grams or grains, two units of measure for projectile weights; a grain is .0648 grams, and a gram is 15.4323 grains.

Sectional density or SD is a measure of a projectiles density, conveying how well an object's mass is distributed through its geometry to overcome resistance. The formula for calculating sectional density is (bullet weight)/(Projectile diameter²), normally calculated using grains as weight and inches as area. Or, if this is too much math, use this calculator

Energy, or force, is a function of mass times acceleration. It is an arbitrary measurement to determine how much potential kinetic energy the bullet has. Normally reported in Foot Pounds or Joules, a bullets energy is a point of contention as to if it is effective or not. In fact, energy does play some role in wounding effects.

Construction generally refers to the design and build of the round. This references type of round in various different types that are difficult to explain at times, but the following reference several common “types”. Please note, there are many different kinds of rounds in each subclass and they can, as such, be confusing. Dont worry, if you’re committed to learning, you will get it eventually.

• Round Nose: A projectile with a rounded nose. Typical military projectile fired from a cartridge until the early 1900s
• Spitzer: A projectile with a pointed nose. This is the most common projectile in modern times.
• Cast Projectile: A standard lead projectile, normally made entirely or mostly of lead.
• Hollow Point: A projectile with a concave nose, commonly without a jacket, designed to expand on impact.
• Jacketed Hollow Points (JHP): A hollowpoint with an encompassing hardened jacket.
• Full Metal Jacket (FMJ): A projectile with a spitzer or round nose, encompassed totally by a hardened metal jacket with various core materials. This is the most common type of ammunition in the world today.\
• Soft Point: A bullet enveloped in a jacket throughout most of the body, except for the nose, which is typically a soft lead, principally for expansion purposes.

Penetration is a function of many factors associated above. Penetration represents the value of perforation a projectile has in soft tissue, commonly given instead in ballistics gel.
There is no definitive formula for calculating penetration; if you would like a penetration figure for your (Small arms) projectile, it is best to ask [user]Puzikas[/user].

Temporary Cavity is a measure of displacement of soft tissue in the human body during projectile travel, representing the “height” of the projectile's displacement. This is almost meaningless; however, it can damage or displace vital material in the body.

Permanent Cavitation is a measure of maximum permanent displacement of tissues in the human body. This may also be termed crush cavity, as tissue affected by this cavity is normally that which has been struck by the projectile in travel.


A number of factors play into the damaging elements of a gunshot wounds; these are varied and numerous. Some if these are common sense, others are unique cases that rarely arise. Some are as follows:

• Shot placement. The area of the body in which the projectile strikes the target.
  
• How many times was the target struck? Once? Twice? Three times? Thirty?
  
• Caliber of the weapon. The projectile itself and its cartridge; obviously some projectiles and cartridges are more lethal than others.
  
• The target themselves. as the individual overweight? Underweight? Do they have any medical conditions like tachycardia or bradycardia? Do they have high bodyfat or low bodyfat? Are they tall or short?
  
• Distance. The distance from the muzzle of the firearm.
  
• Projectile construction. How is the bullet engineered? Whats the design like?
  
• Obstructions. What did the projectile strike in flight, if anything? What was the person wearing? A bullet proof vest? A phonebook? Normal cloths? Denim? Thick winter clothing? Flesh of another person? Nothing?
  
• Angle. What was the striking angle of the wound? Was it a perpendicular strike? Acute? Obtuse?
  
• Medical response. What sort of medical care did the individual receive? How soon did they receive it? Did they even get medical care?

All these and more play cards into a gunshot wounds damaging effects. Dont worry, I am not going to throw you a bunch of curve balls and make you learn about different gunshot wounds from different positions on different people wearing different clothing in different parts of the world. I don’t even do that to the individuals I instruct, I’m sure not going to do that to a bunch of people on the internet.

For all purposes, we will assume that the action is at a perpendicular angle, fired by a shooter of normal size and stature a a target also of normal size and stature at distances specified within the scenarios.

So, you might be wondering:

Why are terminal ballistics important?

Well, in the big picture, they aren't. Artillery and explosions cause more casualties on average than small arms fire in the big picture of warfare. Small Arms, in truth, have not decided wars since the 19th century. Arguably, one could say the last time small arms played a major role in war was the first World War. In a modern setting, the standard military projectile will be equally as lethal as its counterpart for all intents and purposes. 5.56x45mm NATO M855A1, 5.45x39mm 7N22, 5.8x42mm DBP-95 will all, within standard infantry engagements, be perfectly lethal. They function normally and will all be comparably lethal. However, you know what else isn't relevant? The rifle, machine gun, pistol, or so on you use. In fact, none of these matter. These threads don't matter, none of this does at all. But still, we post here, and here we are.

With that out of the way; the majority of terminal ballistics purpose is the medical and forensic field, where we study such things to treat gunshot wound victims better, and to better understand just how projectiles (and indeed, their effects on the human body ) operate. The study and science of projectile trauma leads to significantly better treatment and care of patients who have been shot, and this does not just include in a hospital setting.

With this in mind, I suppose, if you are a writer, this might help you to add an element if the realistic to your writing. It might make you better appreciate how deadly an object, not even one third as thick as your pinky, really can be. It might make you better understand small arms and their history. Or it might just be a fun read, you can now sound smart in front of your friends.



So, how, then, do projectiles kill?

The cause of death from a gunshot wound is loss of brain function. Projectiles achieve this by stemming flow of oxygenated blood to the brain, lowering blood pressure and starving the brain of oxygen, thus killing the target. The other method is simply to sufficiently damage or destroy the brain and/or central nervous system, so as to incapacitate the target; no need to starve the brain of oxygen then, as it is already dead or unable to relay signals.

Traumatic Brain Injuries (TBIs) commonly occur with shots to the head; a TBI occurs when a sudden traumatic force causes damage to the brain. TBI can result when the skull suddenly and violently strikes/is struck by an object, or when an object pierces the skull and enters brain tissue. These cause severe hematomas (ruptured blood vessels) or contusions (bruised brain tissue) within the brain, and have a high lethality rate; approximately 35% of patients who suffer TBIs and die receive them from gunshot wounds; 90% of TBIs inflicted by gunshot wounds are lethal, and the majority of patients never make it to the Emergency Room. For those who do survive the initial trauma, half never make it to the operating table. The primary method by which TBIs kill is blood loss; normally caused by destruction of tissue and severance of vital blood vessels, or by transfer of projectile energy through the brain in the form of a shockwave, thereby sufficiently damaging the brain as to degrade function and cause hemorrhaging.

In wounding, there are several major methods by which the projectile imparts its effects upon the target. Every method relies upon the continued travel of the projectile to a minimum rate of penetration. Commonly, this is defined as 300mm/12 inches of ten-percent ballistics gelatin, a substance that closely mimics the properties of soft tissues in animals and humans. It is important to note that ballistics gelatin, while an excellent approximation, does not mirror the density of the human body perfectly, as it does not model skin nor bone. It is, however, an excellent approximation short of actually shooting, say, a cadaver. This figure is considered the “minimum” to reach and damage important organs in the body; the US Military utilizes a different gelatine, 20-percent, and specifies 250mm/10in as the minimum.

All figures we discuss shall be represented as being ballistics gel.

During the bullets travel through the striking medium, a number of things may occur to create a more effective wound.

The projectile may travel straight through without anything occurring besides its travel. This method has no particular name besides travel. No longer a particularly normal method of wounding, this method creates a relatively normal wound cavity, with little noteworthy performance. This type of wound is highly dependent on the caliber of the bullet, and its velocity; Larger, faster bullets will be far more effective at creating large wound cavities than their smaller counterparts, thereby being more lethal*.

During its travel, the projectile may expand and deform, creating a larger surface area. Similar to above, this projectile relies upon momentum and penetration to create a large wound cavity. These are designed to expand via hydraulic pressure when striking medium, thereby increasing their size and surface area. Commonly, these are hollow point of soft point bullets. As the projectile increases in surface area, so does the resistance on the bullet, which can (and does) limit the penetration of the projectile. However, the larger surface area can create a very large permanent and temporary wound channel; bullets of the hollow-point nature are known to expand at sizes in excess of 20% of their original size, while soft-ponts expand less, but tend to penetrate more. Speaking purely in terminal ballistics, a handgun is generally more effective with hollow point ammunition, a rifle is generally better with soft point ammunition.

Military ammunition, today, generally uses neither of these methods in full, for a myriad of reasons. The principal reason for this is generally that full metal jacket (FMJ) ammunition is in use with pretty much all militaries in the world today, and as such can not take advantage of the principals of expansion, and utilizes more efficient methods of wounding than pure travel.

FMJ offers a number of advantages over its non-FMJ brethren ballistically, being more aerodynamically efficient, retaining ability better, and offering superior penetration of medium. While a number of international laws regulate militaries to using only FMJ ammunition with a non-open, non-concave meplat (The tip of a bullet), I am of the belief that military ammunition eventually would have realized the benefits of FMJ ammunition over other ammunition as body armor became more and more prevalent and we would have arrived at FMJ ammunition as standard eventually.

Some modern military ammunition relies of a principal called yaw. The principal of yawing is quite simple: The penetrating projectile begins to flip nose-to-end, thereby constantly increasing (and decreasing) the volume of the wound. This method may use deformation to accomplish this, where the projectile deforms upon impact to create more lift/downforce on a segment of the projectile, creating the tumbling effect. These projectiles typically penetrate very well, while also creating very large wound channels. This creates an exceptionally large wound channel, which can damage a large number of organ tissues in large amount, and create a very sudden drop in blood pressure (and a large one at that). This method is generally very effective and constant regardless of factors imparted on the projectile; though there are instances in which the bullet fails to yaw.

Other ammunitions may fragment. These ammunition types break apart upon impact with medium and create a number of sub-projectiles that travel through medium. As they travel, they generate a large number number of wound channels than an individual projectile, but, as they lose mass and therefore momentum, they often fail to perforate tissues in significant amount. These wound channels are typically massive in size, but not as long as their yawing counterparts. However, they normally meet and exceed the minimum requirements for penetration, and are are generally considered to be on par with their yawing counterparts.

So, how does modern military ammunition do it?


However they want. They all use, to some degree, all of these methods in order to obtain maximum potential of lethality.

One of the most famous members of this family is the AK-74 series rifles 5.45x39mm cartridge. Some call it “The poison bullet”, and make many allegations as to its lethality. I have heard everything from “They call it that because the Soviets would cover it in fecal matter!” to “The wound kills you days later and you didnt even know it”.

None of these are true in the least. 5.45x39mm is not undeserving of the name “The poison bullet”. It is, arguably, the standard for modern military ammunition lethality. A small caliber, high-velocity projectile, it develops a wound profile far outside what was, prior to its introduction, believed to be capable of conventional full-metal jacket ammunition. How, then, did Soviet designers create such a bullet?

The 5.45x39mm was the result of an experiment that had been ongoing since the late 1950s to develop a small caliber, high-velocity projectile. Many believe 5.45x39mm was developed as an immediate response to the United States adoption of 5.56x45mm; this was not the case. The 5.45x39 was certianly influenced by 5.56x45mms adoption; however, the Soviet Union has been experimenting with the concept for about the same time the United States had.

Testing had indicated the 5mm calibers wound cavity was “undesirable”, being far smaller than then in-service 7.62x39mms; designers solved this problem with a very simple solution.

The projectile utilizes a hollow nose cavity at the immediate front of the projectile, and a center of gravity behind the geometric median point. The hollow nose causes the nose of 5.45x39mm to deform into an “L” shape, creating a surface in which more drag is applied to, causing a destabilization of the projectile in the medium. The rearward center of gravity promotes rotation of the projectile, causing a massive amount of yaw.

The results are massive. 5.45x39 is the ballisticians delight of a projectile, with a long bullet, a high muzzle velocity and excellent characteristics, it is considered by many to be one of the best cartridges ever put into service.

The more Western 5.56x45mm NATO has utilized a number of methods in its service life, and through a number of variants, to achieve the ideal wounding profile. The wounds 5.56x45mm creates are excellent, and it does so via two methods: Fragmentation and yaw. 5.56s Fragmentation occurs ideally at given velocities and distances from the muzzle of the firearm, each dependent on twistrate, barrel length, and so on. For the most part, one can expect fragmentation for a significant portion of typical engagement ranges.

Fragmentation occurs when the striking projectile is acted upon by significant hydraulic force, causing the projectile to deform and break apart. This has more to do with the construction and velocity of the projectile than most anything else; the slower the projectile is going, the less likely it will be to have sufficient force imparted upon its design to deform and fragment. This essentially means fragmentation may be considered unreliable in some ways.

When the projectile does fragment, however, the result is extraordinary. Fragments of various size and shape spread out into their own separate wound channels, causing a large area of crush cavity. Ideally, at least 40% of these fragments, as a measure of the weight of the projectile, should penetrate at least 12 inches/30cm of tissue, with about 16in/40cm being a fairly average penetration distance.


With these methods explained, I can answer a question I was asked.


What Criteria should a projectile meet for a military projectile to be considered terminally effective?

Excellent question. Actually, this is a question that has plagued military ballistics experts for years; at what point is a projectile no longer considered satisfactory in terms of terminal performance?

It is very rare for this question to actually be answered in a cohesive fashion.

The FBI offers a mandate of 12 inches/30cm of penetration of 10% Gel of penetration, but this is not necessarily reflective of the actual wounding capacity of a projectile. The penetration standard as set forth is a recommendation to reliably penetrate human tissue to the point where the projectile will reliably damage organ systems. However, this does not actually reflect how effective a projectile is; it merely advises it can penetrate reliably.

In truth, the penetration is just one of several values associated with the actual line of effectiveness in any projectile. These factors all accumulate to form one of the more reliable metrics for indicating projectile effectiveness: Wound cavity volume.

The wound cavity is the permanent displacement of tissue in the body as a result of the travel of the penetrating projectile. The value associated with this may be used as part of the overall determining factor in actually measuring how effective a projectile is.

There are formulas in my field for calculating the volume wound cavities during theoretical perforation of tissue. They are extremely long and complicated, very tricky to understand, and may not actually yield the correct numbers unless you understand very well what to actually use for measure in given projectiles.

Essentially, one must ascertain the volume of tissue displacement as a result of the projectiles travel. This is difficult and tricky to do, and genuinely creates a large issue for most military planners and designers; You can't actually do so, because nothing is consistent. You may get a range of data for wound volumes from 67cm³ to 145cm³, all because a stiff wind was blowing in the opposite direction.

Because it is so actually complicated to ascertain the dimensions of a wound channel for most people, it is therefore a difficult to answer question. However, I can attempt to quantify it.

Penetration should meet the 12 inch/30cm penetration minimum, and exceed it. Ideally, a 16 inch/40cm penetration should be met, and the wound cavity should not be less than 5.0 Cubic Inches/82cm³ overall. The projectile should attempt to fragment or yaw during its travel, thereby increasing surface area and increasing likelihood the projectile has struck vital areas. This cavitational size is sufficient to allow for rapid loss of blood and will cause incapacitation rapidly enough in a target.

The best way to accomplish this is to simply use a proper sized projectile with a sufficient design to perforate tissue effectively. This means that things like microcalibers (Calibers smaller than 5mm in diameter) are likely not desirable, unless designed in such a way to efficiently cause yaw or fragmentation at a constant rate and in sufficient amount. This means, therefore, one would need to create a projectile of a long caliber to produce increased wounding effects during deformation and destabilization.

You might, too, want to upscale; it may seem like a good idea, then, to move your standard cartridge to larger caliber for the purpose of superseding the minimum. This is problematic from an infantry standpoint due to the inherent weight increase you get with rifles, magazine, and new ammunitions in these new calibers. This is why, generally most modern militaries stick with calibers of the 5mm diameter area; they offer the ideal size, power, and weight ratio for modern militaries and automatic rifle fire.



You might wonder how to engineer a good bullet for the purpose of making a terminally effective round. Dont worry. Its shockingly easy to do so.

For the purpose of military ammunition, one should endeavor to use a Full Metal Jacket projectile with a spitzer nose in really any era after 1910. The projectiles are more aerodynamically efficient, and more terminally efficient than their predecessors. Spitzer projectiles are inherently unstable when traveling through medium due the the tapering shape of the projectile, which creates a slightly rearward center of gravity. This means the nose of the projectile has more lift, which causes yaw. To improve upon this, one should attempt to make the nose of a projectile several calibers in length; normally about 2-2.5 calibers in length is a comfortable medium.

A sectional density of greater than .16 is highly desirable; it ensures the projectile will be able to overcome resistance in travel, allowing for a good penetration rate. This generally means a heavier bullet for a given diameter, which is the result of the materials the bullet is made of. This is more complex and will take some learning to understand, learning outside the scope that this post attempts to encapsulate.

A bullet following these parameters, being of sufficient mass and material construction, when fired at a sufficient velocity, will be able to penetrate the minimum required tissue and create a wound channel properly.

This concludes my general overview of terminal ballistics and introduction to wounding effects. An expansion of any section may be requested and more advanced questions can be answered at request. If any sections need clarifications, please feel free to ask.

[New Visegrad]

What rifle am I most likely to find in the hands of penal companies that fire upon my military?

Century-old bolt-action rifles stained red with the blood of the last round of convicts to be issued them.

[The Archangel Conglomerate]

Stupid question!
How effective would an M/39 style rifle projectile be? That is to say, a lead cored spritzer projectile with a thicker jacket at the front to act as a sort of AP round.

[The Kievan People]

This concludes my general overview of terminal ballistics and introduction to wounding effects. An expansion of any section may be requested and more advanced questions can be answered at request. If any sections need clarifications, please feel free to ask.

A good post.

What.

Did you post in the wrong thread? It's not even about swords and no one will read it.

[Bezombia]

Just read that old list of regulars... That should be updated, don'cha think?

no

[Bezombia]

This is my nomination. There are many like it but this one is mine: Mick Swagger

[The Archangel Conglomerate]

Did you post in the wrong thread? It's not even about swords and no one will read it.

Hey man! I read (most of) it!

[Aqizithiuda]

As many of you know, there are three main stages of ballistics. Internal, or the phase of the projectile within the firearm, External, the phase of the projectile in flight, and Terminal, the final phase of the projectiles flight path, as it strikes (and travels through) the target.

As some of you may not know, I study ballistics. I do so as a maner of hobby and a matter of career; as a civilian shooter, I take interest in internal and external ballistics for long range shooting. As a matter of employment, I study terminal ballistics and trauma.

So what does that mean? Well, quite simply, as a matter of study I deal mostly with traumatic wounds; be these gunshots, stabs, cuts, or blunt force trauma, this is my primary field of study and practice. I am particularly interested in gunshot wounds and their actions therein. I have taken an interest in these during my military career, furthering my knowledge in the post-military years at the collegiate level while employed in law enforcement, and currently am employed in the field.

To put it quite simply: I study how you die.

My knowledge of said actions and study is well known within the guard of the thread, I would think, having broken down many wounding methods and explaining how they work. I think now would be a good time, then, to condense the information to one post, one catch all to help you better understand how it is that bullets wound, what wounding effects are, how the construction of bullets affect their wound profiles, and wound profiles as a whole.

So, let's start.

In terminal performance, various factors contribute to an actual wound profile of a bullet. These terms shall be defined and explained for your understanding.

Velocity is a measure of the projectiles speed, normally measured in feet or meters per second.

Caliber is a measure of the projectiles diameter, normally given in inches or millimeters. It is also used to define cartridges, the name proper of the packaging of the projectile(s) consisting of case, powder, primer, and projectile. It may also be used to define the length of a projectile; A bullet that is 6mm in diameter and is 5 calibers long is 30mm.

Weight or mass is a seldom used term in it of itself. Normally however ma's is used to refer to a projectiles weight. It is normally given in grams or grains, two units of measure for projectile weights; a grain is .0648 grams, and a gram is 15.4323 grains.

Sectional density or SD is a measure of a projectiles density, conveying how well an object's mass is distributed through its geometry to overcome resistance. The formula for calculating sectional density is (bullet weight)/(Projectile diameter²), normally calculated using grains as weight and inches as area. Or, if this is too much math, use this calculator

Energy, or force, is a function of mass times acceleration. It is an arbitrary measurement to determine how much potential kinetic energy the bullet has. Normally reported in Foot Pounds or Joules, a bullets energy is a point of contention as to if it is effective or not. In fact, energy does play some role in wounding effects.

Construction generally refers to the design and build of the round. This references type of round in various different types that are difficult to explain at times, but the following reference several common “types”. Please note, there are many different kinds of rounds in each subclass and they can, as such, be confusing. Dont worry, if you’re committed to learning, you will get it eventually.

• Round Nose: A projectile with a rounded nose. Typical military projectile fired from a cartridge until the early 1900s
• Spitzer: A projectile with a pointed nose. This is the most common projectile in modern times.
• Cast Projectile: A standard lead projectile, normally made entirely or mostly of lead.
• Hollow Point: A projectile with a concave nose, commonly without a jacket, designed to expand on impact.
• Jacketed Hollow Points (JHP): A hollowpoint with an encompassing hardened jacket.
• Full Metal Jacket (FMJ): A projectile with a spitzer or round nose, encompassed totally by a hardened metal jacket with various core materials. This is the most common type of ammunition in the world today.\
• Soft Point: A bullet enveloped in a jacket throughout most of the body, except for the nose, which is typically a soft lead, principally for expansion purposes.

Penetration is a function of many factors associated above. Penetration represents the value of perforation a projectile has in soft tissue, commonly given instead in ballistics gel.
There is no definitive formula for calculating penetration; if you would like a penetration figure for your (Small arms) projectile, it is best to ask [user]Puzikas[/user].

Temporary Cavity is a measure of displacement of soft tissue in the human body during projectile travel, representing the “height” of the projectile's displacement. This is almost meaningless; however, it can damage or displace vital material in the body.

Permanent Cavitation is a measure of maximum permanent displacement of tissues in the human body. This may also be termed crush cavity, as tissue affected by this cavity is normally that which has been struck by the projectile in travel.


A number of factors play into the damaging elements of a gunshot wounds; these are varied and numerous. Some if these are common sense, others are unique cases that rarely arise. Some are as follows:

• Shot placement. The area of the body in which the projectile strikes the target.
  
• How many times was the target struck? Once? Twice? Three times? Thirty?
  
• Caliber of the weapon. The projectile itself and its cartridge; obviously some projectiles and cartridges are more lethal than others.
  
• The target themselves. as the individual overweight? Underweight? Do they have any medical conditions like tachycardia or bradycardia? Do they have high bodyfat or low bodyfat? Are they tall or short?
  
• Distance. The distance from the muzzle of the firearm.
  
• Projectile construction. How is the bullet engineered? Whats the design like?
  
• Obstructions. What did the projectile strike in flight, if anything? What was the person wearing? A bullet proof vest? A phonebook? Normal cloths? Denim? Thick winter clothing? Flesh of another person? Nothing?
  
• Angle. What was the striking angle of the wound? Was it a perpendicular strike? Acute? Obtuse?
  
• Medical response. What sort of medical care did the individual receive? How soon did they receive it? Did they even get medical care?

All these and more play cards into a gunshot wounds damaging effects. Dont worry, I am not going to throw you a bunch of curve balls and make you learn about different gunshot wounds from different positions on different people wearing different clothing in different parts of the world. I don’t even do that to the individuals I instruct, I’m sure not going to do that to a bunch of people on the internet.

For all purposes, we will assume that the action is at a perpendicular angle, fired by a shooter of normal size and stature a a target also of normal size and stature at distances specified within the scenarios.

So, you might be wondering:

Why are terminal ballistics important?

Well, in the big picture, they aren't. Artillery and explosions cause more casualties on average than small arms fire in the big picture of warfare. Small Arms, in truth, have not decided wars since the 19th century. Arguably, one could say the last time small arms played a major role in war was the first World War. In a modern setting, the standard military projectile will be equally as lethal as its counterpart for all intents and purposes. 5.56x45mm NATO M855A1, 5.45x39mm 7N22, 5.8x42mm DBP-95 will all, within standard infantry engagements, be perfectly lethal. They function normally and will all be comparably lethal. However, you know what else isn't relevant? The rifle, machine gun, pistol, or so on you use. In fact, none of these matter. These threads don't matter, none of this does at all. But still, we post here, and here we are.

With that out of the way; the majority of terminal ballistics purpose is the medical and forensic field, where we study such things to treat gunshot wound victims better, and to better understand just how projectiles (and indeed, their effects on the human body ) operate. The study and science of projectile trauma leads to significantly better treatment and care of patients who have been shot, and this does not just include in a hospital setting.

With this in mind, I suppose, if you are a writer, this might help you to add an element if the realistic to your writing. It might make you better appreciate how deadly an object, not even one third as thick as your pinky, really can be. It might make you better understand small arms and their history. Or it might just be a fun read, you can now sound smart in front of your friends.



So, how, then, do projectiles kill?

The cause of death from a gunshot wound is loss of brain function. Projectiles achieve this by stemming flow of oxygenated blood to the brain, lowering blood pressure and starving the brain of oxygen, thus killing the target. The other method is simply to sufficiently damage or destroy the brain and/or central nervous system, so as to incapacitate the target; no need to starve the brain of oxygen then, as it is already dead or unable to relay signals.

Traumatic Brain Injuries (TBIs) commonly occur with shots to the head; a TBI occurs when a sudden traumatic force causes damage to the brain. TBI can result when the skull suddenly and violently strikes/is struck by an object, or when an object pierces the skull and enters brain tissue. These cause severe hematomas (ruptured blood vessels) or contusions (bruised brain tissue) within the brain, and have a high lethality rate; approximately 35% of patients who suffer TBIs and die receive them from gunshot wounds; 90% of TBIs inflicted by gunshot wounds are lethal, and the majority of patients never make it to the Emergency Room. For those who do survive the initial trauma, half never make it to the operating table. The primary method by which TBIs kill is blood loss; normally caused by destruction of tissue and severance of vital blood vessels, or by transfer of projectile energy through the brain in the form of a shockwave, thereby sufficiently damaging the brain as to degrade function and cause hemorrhaging.

In wounding, there are several major methods by which the projectile imparts its effects upon the target. Every method relies upon the continued travel of the projectile to a minimum rate of penetration. Commonly, this is defined as 300mm/12 inches of ten-percent ballistics gelatin, a substance that closely mimics the properties of soft tissues in animals and humans. It is important to note that ballistics gelatin, while an excellent approximation, does not mirror the density of the human body perfectly, as it does not model skin nor bone. It is, however, an excellent approximation short of actually shooting, say, a cadaver. This figure is considered the “minimum” to reach and damage important organs in the body; the US Military utilizes a different gelatine, 20-percent, and specifies 250mm/10in as the minimum.

All figures we discuss shall be represented as being ballistics gel.

During the bullets travel through the striking medium, a number of things may occur to create a more effective wound.

The projectile may travel straight through without anything occurring besides its travel. This method has no particular name besides travel. No longer a particularly normal method of wounding, this method creates a relatively normal wound cavity, with little noteworthy performance. This type of wound is highly dependent on the caliber of the bullet, and its velocity; Larger, faster bullets will be far more effective at creating large wound cavities than their smaller counterparts, thereby being more lethal*.

During its travel, the projectile may expand and deform, creating a larger surface area. Similar to above, this projectile relies upon momentum and penetration to create a large wound cavity. These are designed to expand via hydraulic pressure when striking medium, thereby increasing their size and surface area. Commonly, these are hollow point of soft point bullets. As the projectile increases in surface area, so does the resistance on the bullet, which can (and does) limit the penetration of the projectile. However, the larger surface area can create a very large permanent and temporary wound channel; bullets of the hollow-point nature are known to expand at sizes in excess of 20% of their original size, while soft-ponts expand less, but tend to penetrate more. Speaking purely in terminal ballistics, a handgun is generally more effective with hollow point ammunition, a rifle is generally better with soft point ammunition.

Military ammunition, today, generally uses neither of these methods in full, for a myriad of reasons. The principal reason for this is generally that full metal jacket (FMJ) ammunition is in use with pretty much all militaries in the world today, and as such can not take advantage of the principals of expansion, and utilizes more efficient methods of wounding than pure travel.

FMJ offers a number of advantages over its non-FMJ brethren ballistically, being more aerodynamically efficient, retaining ability better, and offering superior penetration of medium. While a number of international laws regulate militaries to using only FMJ ammunition with a non-open, non-concave meplat (The tip of a bullet), I am of the belief that military ammunition eventually would have realized the benefits of FMJ ammunition over other ammunition as body armor became more and more prevalent and we would have arrived at FMJ ammunition as standard eventually.

Some modern military ammunition relies of a principal called yaw. The principal of yawing is quite simple: The penetrating projectile begins to flip nose-to-end, thereby constantly increasing (and decreasing) the volume of the wound. This method may use deformation to accomplish this, where the projectile deforms upon impact to create more lift/downforce on a segment of the projectile, creating the tumbling effect. These projectiles typically penetrate very well, while also creating very large wound channels. This creates an exceptionally large wound channel, which can damage a large number of organ tissues in large amount, and create a very sudden drop in blood pressure (and a large one at that). This method is generally very effective and constant regardless of factors imparted on the projectile; though there are instances in which the bullet fails to yaw.

Other ammunitions may fragment. These ammunition types break apart upon impact with medium and create a number of sub-projectiles that travel through medium. As they travel, they generate a large number number of wound channels than an individual projectile, but, as they lose mass and therefore momentum, they often fail to perforate tissues in significant amount. These wound channels are typically massive in size, but not as long as their yawing counterparts. However, they normally meet and exceed the minimum requirements for penetration, and are are generally considered to be on par with their yawing counterparts.

So, how does modern military ammunition do it?


However they want. They all use, to some degree, all of these methods in order to obtain maximum potential of lethality.

One of the most famous members of this family is the AK-74 series rifles 5.45x39mm cartridge. Some call it “The poison bullet”, and make many allegations as to its lethality. I have heard everything from “They call it that because the Soviets would cover it in fecal matter!” to “The wound kills you days later and you didnt even know it”.

None of these are true in the least. 5.45x39mm is not undeserving of the name “The poison bullet”. It is, arguably, the standard for modern military ammunition lethality. A small caliber, high-velocity projectile, it develops a wound profile far outside what was, prior to its introduction, believed to be capable of conventional full-metal jacket ammunition. How, then, did Soviet designers create such a bullet?

The 5.45x39mm was the result of an experiment that had been ongoing since the late 1950s to develop a small caliber, high-velocity projectile. Many believe 5.45x39mm was developed as an immediate response to the United States adoption of 5.56x45mm; this was not the case. The 5.45x39 was certianly influenced by 5.56x45mms adoption; however, the Soviet Union has been experimenting with the concept for about the same time the United States had.

Testing had indicated the 5mm calibers wound cavity was “undesirable”, being far smaller than then in-service 7.62x39mms; designers solved this problem with a very simple solution.

The projectile utilizes a hollow nose cavity at the immediate front of the projectile, and a center of gravity behind the geometric median point. The hollow nose causes the nose of 5.45x39mm to deform into an “L” shape, creating a surface in which more drag is applied to, causing a destabilization of the projectile in the medium. The rearward center of gravity promotes rotation of the projectile, causing a massive amount of yaw.

The results are massive. 5.45x39 is the ballisticians delight of a projectile, with a long bullet, a high muzzle velocity and excellent characteristics, it is considered by many to be one of the best cartridges ever put into service.

The more Western 5.56x45mm NATO has utilized a number of methods in its service life, and through a number of variants, to achieve the ideal wounding profile. The wounds 5.56x45mm creates are excellent, and it does so via two methods: Fragmentation and yaw. 5.56s Fragmentation occurs ideally at given velocities and distances from the muzzle of the firearm, each dependent on twistrate, barrel length, and so on. For the most part, one can expect fragmentation for a significant portion of typical engagement ranges.

Fragmentation occurs when the striking projectile is acted upon by significant hydraulic force, causing the projectile to deform and break apart. This has more to do with the construction and velocity of the projectile than most anything else; the slower the projectile is going, the less likely it will be to have sufficient force imparted upon its design to deform and fragment. This essentially means fragmentation may be considered unreliable in some ways.

When the projectile does fragment, however, the result is extraordinary. Fragments of various size and shape spread out into their own separate wound channels, causing a large area of crush cavity. Ideally, at least 40% of these fragments, as a measure of the weight of the projectile, should penetrate at least 12 inches/30cm of tissue, with about 16in/40cm being a fairly average penetration distance.


With these methods explained, I can answer a question I was asked.


What Criteria should a projectile meet for a military projectile to be considered terminally effective?

Excellent question. Actually, this is a question that has plagued military ballistics experts for years; at what point is a projectile no longer considered satisfactory in terms of terminal performance?

It is very rare for this question to actually be answered in a cohesive fashion.

The FBI offers a mandate of 12 inches/30cm of penetration of 10% Gel of penetration, but this is not necessarily reflective of the actual wounding capacity of a projectile. The penetration standard as set forth is a recommendation to reliably penetrate human tissue to the point where the projectile will reliably damage organ systems. However, this does not actually reflect how effective a projectile is; it merely advises it can penetrate reliably.

In truth, the penetration is just one of several values associated with the actual line of effectiveness in any projectile. These factors all accumulate to form one of the more reliable metrics for indicating projectile effectiveness: Wound cavity volume.

The wound cavity is the permanent displacement of tissue in the body as a result of the travel of the penetrating projectile. The value associated with this may be used as part of the overall determining factor in actually measuring how effective a projectile is.

There are formulas in my field for calculating the volume wound cavities during theoretical perforation of tissue. They are extremely long and complicated, very tricky to understand, and may not actually yield the correct numbers unless you understand very well what to actually use for measure in given projectiles.

Essentially, one must ascertain the volume of tissue displacement as a result of the projectiles travel. This is difficult and tricky to do, and genuinely creates a large issue for most military planners and designers; You can't actually do so, because nothing is consistent. You may get a range of data for wound volumes from 67cm³ to 145cm³, all because a stiff wind was blowing in the opposite direction.

Because it is so actually complicated to ascertain the dimensions of a wound channel for most people, it is therefore a difficult to answer question. However, I can attempt to quantify it.

Penetration should meet the 12 inch/30cm penetration minimum, and exceed it. Ideally, a 16 inch/40cm penetration should be met, and the wound cavity should not be less than 5.0 Cubic Inches/82cm³ overall. The projectile should attempt to fragment or yaw during its travel, thereby increasing surface area and increasing likelihood the projectile has struck vital areas. This cavitational size is sufficient to allow for rapid loss of blood and will cause incapacitation rapidly enough in a target.

The best way to accomplish this is to simply use a proper sized projectile with a sufficient design to perforate tissue effectively. This means that things like microcalibers (Calibers smaller than 5mm in diameter) are likely not desirable, unless designed in such a way to efficiently cause yaw or fragmentation at a constant rate and in sufficient amount. This means, therefore, one would need to create a projectile of a long caliber to produce increased wounding effects during deformation and destabilization.

You might, too, want to upscale; it may seem like a good idea, then, to move your standard cartridge to larger caliber for the purpose of superseding the minimum. This is problematic from an infantry standpoint due to the inherent weight increase you get with rifles, magazine, and new ammunitions in these new calibers. This is why, generally most modern militaries stick with calibers of the 5mm diameter area; they offer the ideal size, power, and weight ratio for modern militaries and automatic rifle fire.



You might wonder how to engineer a good bullet for the purpose of making a terminally effective round. Dont worry. Its shockingly easy to do so.

For the purpose of military ammunition, one should endeavor to use a Full Metal Jacket projectile with a spitzer nose in really any era after 1910. The projectiles are more aerodynamically efficient, and more terminally efficient than their predecessors. Spitzer projectiles are inherently unstable when traveling through medium due the the tapering shape of the projectile, which creates a slightly rearward center of gravity. This means the nose of the projectile has more lift, which causes yaw. To improve upon this, one should attempt to make the nose of a projectile several calibers in length; normally about 2-2.5 calibers in length is a comfortable medium.

A sectional density of greater than .16 is highly desirable; it ensures the projectile will be able to overcome resistance in travel, allowing for a good penetration rate. This generally means a heavier bullet for a given diameter, which is the result of the materials the bullet is made of. This is more complex and will take some learning to understand, learning outside the scope that this post attempts to encapsulate.

A bullet following these parameters, being of sufficient mass and material construction, when fired at a sufficient velocity, will be able to penetrate the minimum required tissue and create a wound channel properly.

This concludes my general overview of terminal ballistics and introduction to wounding effects. An expansion of any section may be requested and more advanced questions can be answered at request. If any sections need clarifications, please feel free to ask.

That was an excellent post, clear and concise with pretty much all the info we'd ever want.

It does have me wondering how a pound's performance in 20% gel differs from 10% gel, though.

[Padnak]

Id like to see you try to force me to do anything.
But I guess I could.

Dooo eeeet

As many of you know, there are three main stages of ballistics. Internal, or the phase of the projectile within the firearm, External, the phase of the projectile in flight, and Terminal, the final phase of the projectiles flight path, as it strikes (and travels through) the target.

As some of you may not know, I study ballistics. I do so as a maner of hobby and a matter of career; as a civilian shooter, I take interest in internal and external ballistics for long range shooting. As a matter of employment, I study terminal ballistics and trauma.

So what does that mean? Well, quite simply, as a matter of study I deal mostly with traumatic wounds; be these gunshots, stabs, cuts, or blunt force trauma, this is my primary field of study and practice. I am particularly interested in gunshot wounds and their actions therein. I have taken an interest in these during my military career, furthering my knowledge in the post-military years at the collegiate level while employed in law enforcement, and currently am employed in the field.

To put it quite simply: I study how you die.

My knowledge of said actions and study is well known within the guard of the thread, I would think, having broken down many wounding methods and explaining how they work. I think now would be a good time, then, to condense the information to one post, one catch all to help you better understand how it is that bullets wound, what wounding effects are, how the construction of bullets affect their wound profiles, and wound profiles as a whole.

So, let's start.

In terminal performance, various factors contribute to an actual wound profile of a bullet. These terms shall be defined and explained for your understanding.

Velocity is a measure of the projectiles speed, normally measured in feet or meters per second.

Caliber is a measure of the projectiles diameter, normally given in inches or millimeters. It is also used to define cartridges, the name proper of the packaging of the projectile(s) consisting of case, powder, primer, and projectile. It may also be used to define the length of a projectile; A bullet that is 6mm in diameter and is 5 calibers long is 30mm.

Weight or mass is a seldom used term in it of itself. Normally however ma's is used to refer to a projectiles weight. It is normally given in grams or grains, two units of measure for projectile weights; a grain is .0648 grams, and a gram is 15.4323 grains.

Sectional density or SD is a measure of a projectiles density, conveying how well an object's mass is distributed through its geometry to overcome resistance. The formula for calculating sectional density is (bullet weight)/(Projectile diameter²), normally calculated using grains as weight and inches as area. Or, if this is too much math, use this calculator

Energy, or force, is a function of mass times acceleration. It is an arbitrary measurement to determine how much potential kinetic energy the bullet has. Normally reported in Foot Pounds or Joules, a bullets energy is a point of contention as to if it is effective or not. In fact, energy does play some role in wounding effects.

Construction generally refers to the design and build of the round. This references type of round in various different types that are difficult to explain at times, but the following reference several common “types”. Please note, there are many different kinds of rounds in each subclass and they can, as such, be confusing. Dont worry, if you’re committed to learning, you will get it eventually.

• Round Nose: A projectile with a rounded nose. Typical military projectile fired from a cartridge until the early 1900s
• Spitzer: A projectile with a pointed nose. This is the most common projectile in modern times.
• Cast Projectile: A standard lead projectile, normally made entirely or mostly of lead.
• Hollow Point: A projectile with a concave nose, commonly without a jacket, designed to expand on impact.
• Jacketed Hollow Points (JHP): A hollowpoint with an encompassing hardened jacket.
• Full Metal Jacket (FMJ): A projectile with a spitzer or round nose, encompassed totally by a hardened metal jacket with various core materials. This is the most common type of ammunition in the world today.\
• Soft Point: A bullet enveloped in a jacket throughout most of the body, except for the nose, which is typically a soft lead, principally for expansion purposes.

Penetration is a function of many factors associated above. Penetration represents the value of perforation a projectile has in soft tissue, commonly given instead in ballistics gel.
There is no definitive formula for calculating penetration; if you would like a penetration figure for your (Small arms) projectile, it is best to ask [user]Puzikas[/user].

Temporary Cavity is a measure of displacement of soft tissue in the human body during projectile travel, representing the “height” of the projectile's displacement. This is almost meaningless; however, it can damage or displace vital material in the body.

Permanent Cavitation is a measure of maximum permanent displacement of tissues in the human body. This may also be termed crush cavity, as tissue affected by this cavity is normally that which has been struck by the projectile in travel.


A number of factors play into the damaging elements of a gunshot wounds; these are varied and numerous. Some if these are common sense, others are unique cases that rarely arise. Some are as follows:

• Shot placement. The area of the body in which the projectile strikes the target.
  
• How many times was the target struck? Once? Twice? Three times? Thirty?
  
• Caliber of the weapon. The projectile itself and its cartridge; obviously some projectiles and cartridges are more lethal than others.
  
• The target themselves. as the individual overweight? Underweight? Do they have any medical conditions like tachycardia or bradycardia? Do they have high bodyfat or low bodyfat? Are they tall or short?
  
• Distance. The distance from the muzzle of the firearm.
  
• Projectile construction. How is the bullet engineered? Whats the design like?
  
• Obstructions. What did the projectile strike in flight, if anything? What was the person wearing? A bullet proof vest? A phonebook? Normal cloths? Denim? Thick winter clothing? Flesh of another person? Nothing?
  
• Angle. What was the striking angle of the wound? Was it a perpendicular strike? Acute? Obtuse?
  
• Medical response. What sort of medical care did the individual receive? How soon did they receive it? Did they even get medical care?

All these and more play cards into a gunshot wounds damaging effects. Dont worry, I am not going to throw you a bunch of curve balls and make you learn about different gunshot wounds from different positions on different people wearing different clothing in different parts of the world. I don’t even do that to the individuals I instruct, I’m sure not going to do that to a bunch of people on the internet.

For all purposes, we will assume that the action is at a perpendicular angle, fired by a shooter of normal size and stature a a target also of normal size and stature at distances specified within the scenarios.

So, you might be wondering:

Why are terminal ballistics important?

Well, in the big picture, they aren't. Artillery and explosions cause more casualties on average than small arms fire in the big picture of warfare. Small Arms, in truth, have not decided wars since the 19th century. Arguably, one could say the last time small arms played a major role in war was the first World War. In a modern setting, the standard military projectile will be equally as lethal as its counterpart for all intents and purposes. 5.56x45mm NATO M855A1, 5.45x39mm 7N22, 5.8x42mm DBP-95 will all, within standard infantry engagements, be perfectly lethal. They function normally and will all be comparably lethal. However, you know what else isn't relevant? The rifle, machine gun, pistol, or so on you use. In fact, none of these matter. These threads don't matter, none of this does at all. But still, we post here, and here we are.

With that out of the way; the majority of terminal ballistics purpose is the medical and forensic field, where we study such things to treat gunshot wound victims better, and to better understand just how projectiles (and indeed, their effects on the human body ) operate. The study and science of projectile trauma leads to significantly better treatment and care of patients who have been shot, and this does not just include in a hospital setting.

With this in mind, I suppose, if you are a writer, this might help you to add an element if the realistic to your writing. It might make you better appreciate how deadly an object, not even one third as thick as your pinky, really can be. It might make you better understand small arms and their history. Or it might just be a fun read, you can now sound smart in front of your friends.



So, how, then, do projectiles kill?

The cause of death from a gunshot wound is loss of brain function. Projectiles achieve this by stemming flow of oxygenated blood to the brain, lowering blood pressure and starving the brain of oxygen, thus killing the target. The other method is simply to sufficiently damage or destroy the brain and/or central nervous system, so as to incapacitate the target; no need to starve the brain of oxygen then, as it is already dead or unable to relay signals.

Traumatic Brain Injuries (TBIs) commonly occur with shots to the head; a TBI occurs when a sudden traumatic force causes damage to the brain. TBI can result when the skull suddenly and violently strikes/is struck by an object, or when an object pierces the skull and enters brain tissue. These cause severe hematomas (ruptured blood vessels) or contusions (bruised brain tissue) within the brain, and have a high lethality rate; approximately 35% of patients who suffer TBIs and die receive them from gunshot wounds; 90% of TBIs inflicted by gunshot wounds are lethal, and the majority of patients never make it to the Emergency Room. For those who do survive the initial trauma, half never make it to the operating table. The primary method by which TBIs kill is blood loss; normally caused by destruction of tissue and severance of vital blood vessels, or by transfer of projectile energy through the brain in the form of a shockwave, thereby sufficiently damaging the brain as to degrade function and cause hemorrhaging.

In wounding, there are several major methods by which the projectile imparts its effects upon the target. Every method relies upon the continued travel of the projectile to a minimum rate of penetration. Commonly, this is defined as 300mm/12 inches of ten-percent ballistics gelatin, a substance that closely mimics the properties of soft tissues in animals and humans. It is important to note that ballistics gelatin, while an excellent approximation, does not mirror the density of the human body perfectly, as it does not model skin nor bone. It is, however, an excellent approximation short of actually shooting, say, a cadaver. This figure is considered the “minimum” to reach and damage important organs in the body; the US Military utilizes a different gelatine, 20-percent, and specifies 250mm/10in as the minimum.

All figures we discuss shall be represented as being ballistics gel.

During the bullets travel through the striking medium, a number of things may occur to create a more effective wound.

The projectile may travel straight through without anything occurring besides its travel. This method has no particular name besides travel. No longer a particularly normal method of wounding, this method creates a relatively normal wound cavity, with little noteworthy performance. This type of wound is highly dependent on the caliber of the bullet, and its velocity; Larger, faster bullets will be far more effective at creating large wound cavities than their smaller counterparts, thereby being more lethal*.

During its travel, the projectile may expand and deform, creating a larger surface area. Similar to above, this projectile relies upon momentum and penetration to create a large wound cavity. These are designed to expand via hydraulic pressure when striking medium, thereby increasing their size and surface area. Commonly, these are hollow point of soft point bullets. As the projectile increases in surface area, so does the resistance on the bullet, which can (and does) limit the penetration of the projectile. However, the larger surface area can create a very large permanent and temporary wound channel; bullets of the hollow-point nature are known to expand at sizes in excess of 20% of their original size, while soft-ponts expand less, but tend to penetrate more. Speaking purely in terminal ballistics, a handgun is generally more effective with hollow point ammunition, a rifle is generally better with soft point ammunition.

Military ammunition, today, generally uses neither of these methods in full, for a myriad of reasons. The principal reason for this is generally that full metal jacket (FMJ) ammunition is in use with pretty much all militaries in the world today, and as such can not take advantage of the principals of expansion, and utilizes more efficient methods of wounding than pure travel.

FMJ offers a number of advantages over its non-FMJ brethren ballistically, being more aerodynamically efficient, retaining ability better, and offering superior penetration of medium. While a number of international laws regulate militaries to using only FMJ ammunition with a non-open, non-concave meplat (The tip of a bullet), I am of the belief that military ammunition eventually would have realized the benefits of FMJ ammunition over other ammunition as body armor became more and more prevalent and we would have arrived at FMJ ammunition as standard eventually.

Some modern military ammunition relies of a principal called yaw. The principal of yawing is quite simple: The penetrating projectile begins to flip nose-to-end, thereby constantly increasing (and decreasing) the volume of the wound. This method may use deformation to accomplish this, where the projectile deforms upon impact to create more lift/downforce on a segment of the projectile, creating the tumbling effect. These projectiles typically penetrate very well, while also creating very large wound channels. This creates an exceptionally large wound channel, which can damage a large number of organ tissues in large amount, and create a very sudden drop in blood pressure (and a large one at that). This method is generally very effective and constant regardless of factors imparted on the projectile; though there are instances in which the bullet fails to yaw.

Other ammunitions may fragment. These ammunition types break apart upon impact with medium and create a number of sub-projectiles that travel through medium. As they travel, they generate a large number number of wound channels than an individual projectile, but, as they lose mass and therefore momentum, they often fail to perforate tissues in significant amount. These wound channels are typically massive in size, but not as long as their yawing counterparts. However, they normally meet and exceed the minimum requirements for penetration, and are are generally considered to be on par with their yawing counterparts.

So, how does modern military ammunition do it?


However they want. They all use, to some degree, all of these methods in order to obtain maximum potential of lethality.

One of the most famous members of this family is the AK-74 series rifles 5.45x39mm cartridge. Some call it “The poison bullet”, and make many allegations as to its lethality. I have heard everything from “They call it that because the Soviets would cover it in fecal matter!” to “The wound kills you days later and you didnt even know it”.

None of these are true in the least. 5.45x39mm is not undeserving of the name “The poison bullet”. It is, arguably, the standard for modern military ammunition lethality. A small caliber, high-velocity projectile, it develops a wound profile far outside what was, prior to its introduction, believed to be capable of conventional full-metal jacket ammunition. How, then, did Soviet designers create such a bullet?

The 5.45x39mm was the result of an experiment that had been ongoing since the late 1950s to develop a small caliber, high-velocity projectile. Many believe 5.45x39mm was developed as an immediate response to the United States adoption of 5.56x45mm; this was not the case. The 5.45x39 was certianly influenced by 5.56x45mms adoption; however, the Soviet Union has been experimenting with the concept for about the same time the United States had.

Testing had indicated the 5mm calibers wound cavity was “undesirable”, being far smaller than then in-service 7.62x39mms; designers solved this problem with a very simple solution.

The projectile utilizes a hollow nose cavity at the immediate front of the projectile, and a center of gravity behind the geometric median point. The hollow nose causes the nose of 5.45x39mm to deform into an “L” shape, creating a surface in which more drag is applied to, causing a destabilization of the projectile in the medium. The rearward center of gravity promotes rotation of the projectile, causing a massive amount of yaw.

The results are massive. 5.45x39 is the ballisticians delight of a projectile, with a long bullet, a high muzzle velocity and excellent characteristics, it is considered by many to be one of the best cartridges ever put into service.

The more Western 5.56x45mm NATO has utilized a number of methods in its service life, and through a number of variants, to achieve the ideal wounding profile. The wounds 5.56x45mm creates are excellent, and it does so via two methods: Fragmentation and yaw. 5.56s Fragmentation occurs ideally at given velocities and distances from the muzzle of the firearm, each dependent on twistrate, barrel length, and so on. For the most part, one can expect fragmentation for a significant portion of typical engagement ranges.

Fragmentation occurs when the striking projectile is acted upon by significant hydraulic force, causing the projectile to deform and break apart. This has more to do with the construction and velocity of the projectile than most anything else; the slower the projectile is going, the less likely it will be to have sufficient force imparted upon its design to deform and fragment. This essentially means fragmentation may be considered unreliable in some ways.

When the projectile does fragment, however, the result is extraordinary. Fragments of various size and shape spread out into their own separate wound channels, causing a large area of crush cavity. Ideally, at least 40% of these fragments, as a measure of the weight of the projectile, should penetrate at least 12 inches/30cm of tissue, with about 16in/40cm being a fairly average penetration distance.


With these methods explained, I can answer a question I was asked.


What Criteria should a projectile meet for a military projectile to be considered terminally effective?

Excellent question. Actually, this is a question that has plagued military ballistics experts for years; at what point is a projectile no longer considered satisfactory in terms of terminal performance?

It is very rare for this question to actually be answered in a cohesive fashion.

The FBI offers a mandate of 12 inches/30cm of penetration of 10% Gel of penetration, but this is not necessarily reflective of the actual wounding capacity of a projectile. The penetration standard as set forth is a recommendation to reliably penetrate human tissue to the point where the projectile will reliably damage organ systems. However, this does not actually reflect how effective a projectile is; it merely advises it can penetrate reliably.

In truth, the penetration is just one of several values associated with the actual line of effectiveness in any projectile. These factors all accumulate to form one of the more reliable metrics for indicating projectile effectiveness: Wound cavity volume.

The wound cavity is the permanent displacement of tissue in the body as a result of the travel of the penetrating projectile. The value associated with this may be used as part of the overall determining factor in actually measuring how effective a projectile is.

There are formulas in my field for calculating the volume wound cavities during theoretical perforation of tissue. They are extremely long and complicated, very tricky to understand, and may not actually yield the correct numbers unless you understand very well what to actually use for measure in given projectiles.

Essentially, one must ascertain the volume of tissue displacement as a result of the projectiles travel. This is difficult and tricky to do, and genuinely creates a large issue for most military planners and designers; You can't actually do so, because nothing is consistent. You may get a range of data for wound volumes from 67cm³ to 145cm³, all because a stiff wind was blowing in the opposite direction.

Because it is so actually complicated to ascertain the dimensions of a wound channel for most people, it is therefore a difficult to answer question. However, I can attempt to quantify it.

Penetration should meet the 12 inch/30cm penetration minimum, and exceed it. Ideally, a 16 inch/40cm penetration should be met, and the wound cavity should not be less than 5.0 Cubic Inches/82cm³ overall. The projectile should attempt to fragment or yaw during its travel, thereby increasing surface area and increasing likelihood the projectile has struck vital areas. This cavitational size is sufficient to allow for rapid loss of blood and will cause incapacitation rapidly enough in a target.

The best way to accomplish this is to simply use a proper sized projectile with a sufficient design to perforate tissue effectively. This means that things like microcalibers (Calibers smaller than 5mm in diameter) are likely not desirable, unless designed in such a way to efficiently cause yaw or fragmentation at a constant rate and in sufficient amount. This means, therefore, one would need to create a projectile of a long caliber to produce increased wounding effects during deformation and destabilization.

You might, too, want to upscale; it may seem like a good idea, then, to move your standard cartridge to larger caliber for the purpose of superseding the minimum. This is problematic from an infantry standpoint due to the inherent weight increase you get with rifles, magazine, and new ammunitions in these new calibers. This is why, generally most modern militaries stick with calibers of the 5mm diameter area; they offer the ideal size, power, and weight ratio for modern militaries and automatic rifle fire.



You might wonder how to engineer a good bullet for the purpose of making a terminally effective round. Dont worry. Its shockingly easy to do so.

For the purpose of military ammunition, one should endeavor to use a Full Metal Jacket projectile with a spitzer nose in really any era after 1910. The projectiles are more aerodynamically efficient, and more terminally efficient than their predecessors. Spitzer projectiles are inherently unstable when traveling through medium due the the tapering shape of the projectile, which creates a slightly rearward center of gravity. This means the nose of the projectile has more lift, which causes yaw. To improve upon this, one should attempt to make the nose of a projectile several calibers in length; normally about 2-2.5 calibers in length is a comfortable medium.

A sectional density of greater than .16 is highly desirable; it ensures the projectile will be able to overcome resistance in travel, allowing for a good penetration rate. This generally means a heavier bullet for a given diameter, which is the result of the materials the bullet is made of. This is more complex and will take some learning to understand, learning outside the scope that this post attempts to encapsulate.

A bullet following these parameters, being of sufficient mass and material construction, when fired at a sufficient velocity, will be able to penetrate the minimum required tissue and create a wound channel properly.

This concludes my general overview of terminal ballistics and introduction to wounding effects. An expansion of any section may be requested and more advanced questions can be answered at request. If any sections need clarifications, please feel free to ask.

That was an excellent post, clear and concise with pretty much all the info we'd ever want.

It does have me wondering how a pound's performance in 20% gel differs from 10% gel, though.

10/10 Quality post

[Doppio Giudici]

This concludes my general overview of terminal ballistics and introduction to wounding effects. An expansion of any section may be requested and more advanced questions can be answered at request. If any sections need clarifications, please feel free to ask.

A good post.

What.

Did you post in the wrong thread? It's not even about swords and no one will read it.

I read about the militaries recent ammo improvements and it seems that people in third world counties look like me.

Very bony, not that fat or tall.

Might explain the thinner, but denser gel they use.

[Nirvash Type TheEND]

It's Puz's thing.

You never take someone else's thing.

Unless you're Nirv. Then you just try.

You. Me. The Flagpole. After school.

[Nirvash Type TheEND]

As many of you know, there are three main stages of ballistics. Internal, or the phase of the projectile within the firearm, External, the phase of the projectile in flight, and Terminal, the final phase of the projectiles flight path, as it strikes (and travels through) the target.

As some of you may not know, I study ballistics. I do so as a maner of hobby and a matter of career; as a civilian shooter, I take interest in internal and external ballistics for long range shooting. As a matter of employment, I study terminal ballistics and trauma.

So what does that mean? Well, quite simply, as a matter of study I deal mostly with traumatic wounds; be these gunshots, stabs, cuts, or blunt force trauma, this is my primary field of study and practice. I am particularly interested in gunshot wounds and their actions therein. I have taken an interest in these during my military career, furthering my knowledge in the post-military years at the collegiate level while employed in law enforcement, and currently am employed in the field.

To put it quite simply: I study how you die.

My knowledge of said actions and study is well known within the guard of the thread, I would think, having broken down many wounding methods and explaining how they work. I think now would be a good time, then, to condense the information to one post, one catch all to help you better understand how it is that bullets wound, what wounding effects are, how the construction of bullets affect their wound profiles, and wound profiles as a whole.

So, let's start.

In terminal performance, various factors contribute to an actual wound profile of a bullet. These terms shall be defined and explained for your understanding.

Velocity is a measure of the projectiles speed, normally measured in feet or meters per second.

Caliber is a measure of the projectiles diameter, normally given in inches or millimeters. It is also used to define cartridges, the name proper of the packaging of the projectile(s) consisting of case, powder, primer, and projectile. It may also be used to define the length of a projectile; A bullet that is 6mm in diameter and is 5 calibers long is 30mm.

Weight or mass is a seldom used term in it of itself. Normally however ma's is used to refer to a projectiles weight. It is normally given in grams or grains, two units of measure for projectile weights; a grain is .0648 grams, and a gram is 15.4323 grains.

Sectional density or SD is a measure of a projectiles density, conveying how well an object's mass is distributed through its geometry to overcome resistance. The formula for calculating sectional density is (bullet weight)/(Projectile diameter²), normally calculated using grains as weight and inches as area. Or, if this is too much math, use this calculator

Energy, or force, is a function of mass times acceleration. It is an arbitrary measurement to determine how much potential kinetic energy the bullet has. Normally reported in Foot Pounds or Joules, a bullets energy is a point of contention as to if it is effective or not. In fact, energy does play some role in wounding effects.

Construction generally refers to the design and build of the round. This references type of round in various different types that are difficult to explain at times, but the following reference several common “types”. Please note, there are many different kinds of rounds in each subclass and they can, as such, be confusing. Dont worry, if you’re committed to learning, you will get it eventually.

• Round Nose: A projectile with a rounded nose. Typical military projectile fired from a cartridge until the early 1900s
• Spitzer: A projectile with a pointed nose. This is the most common projectile in modern times.
• Cast Projectile: A standard lead projectile, normally made entirely or mostly of lead.
• Hollow Point: A projectile with a concave nose, commonly without a jacket, designed to expand on impact.
• Jacketed Hollow Points (JHP): A hollowpoint with an encompassing hardened jacket.
• Full Metal Jacket (FMJ): A projectile with a spitzer or round nose, encompassed totally by a hardened metal jacket with various core materials. This is the most common type of ammunition in the world today.\
• Soft Point: A bullet enveloped in a jacket throughout most of the body, except for the nose, which is typically a soft lead, principally for expansion purposes.

Penetration is a function of many factors associated above. Penetration represents the value of perforation a projectile has in soft tissue, commonly given instead in ballistics gel.
There is no definitive formula for calculating penetration; if you would like a penetration figure for your (Small arms) projectile, it is best to ask [user]Puzikas[/user].

Temporary Cavity is a measure of displacement of soft tissue in the human body during projectile travel, representing the “height” of the projectile's displacement. This is almost meaningless; however, it can damage or displace vital material in the body.

Permanent Cavitation is a measure of maximum permanent displacement of tissues in the human body. This may also be termed crush cavity, as tissue affected by this cavity is normally that which has been struck by the projectile in travel.


A number of factors play into the damaging elements of a gunshot wounds; these are varied and numerous. Some if these are common sense, others are unique cases that rarely arise. Some are as follows:

• Shot placement. The area of the body in which the projectile strikes the target.
  
• How many times was the target struck? Once? Twice? Three times? Thirty?
  
• Caliber of the weapon. The projectile itself and its cartridge; obviously some projectiles and cartridges are more lethal than others.
  
• The target themselves. as the individual overweight? Underweight? Do they have any medical conditions like tachycardia or bradycardia? Do they have high bodyfat or low bodyfat? Are they tall or short?
  
• Distance. The distance from the muzzle of the firearm.
  
• Projectile construction. How is the bullet engineered? Whats the design like?
  
• Obstructions. What did the projectile strike in flight, if anything? What was the person wearing? A bullet proof vest? A phonebook? Normal cloths? Denim? Thick winter clothing? Flesh of another person? Nothing?
  
• Angle. What was the striking angle of the wound? Was it a perpendicular strike? Acute? Obtuse?
  
• Medical response. What sort of medical care did the individual receive? How soon did they receive it? Did they even get medical care?

All these and more play cards into a gunshot wounds damaging effects. Dont worry, I am not going to throw you a bunch of curve balls and make you learn about different gunshot wounds from different positions on different people wearing different clothing in different parts of the world. I don’t even do that to the individuals I instruct, I’m sure not going to do that to a bunch of people on the internet.

For all purposes, we will assume that the action is at a perpendicular angle, fired by a shooter of normal size and stature a a target also of normal size and stature at distances specified within the scenarios.

So, you might be wondering:

Why are terminal ballistics important?

Well, in the big picture, they aren't. Artillery and explosions cause more casualties on average than small arms fire in the big picture of warfare. Small Arms, in truth, have not decided wars since the 19th century. Arguably, one could say the last time small arms played a major role in war was the first World War. In a modern setting, the standard military projectile will be equally as lethal as its counterpart for all intents and purposes. 5.56x45mm NATO M855A1, 5.45x39mm 7N22, 5.8x42mm DBP-95 will all, within standard infantry engagements, be perfectly lethal. They function normally and will all be comparably lethal. However, you know what else isn't relevant? The rifle, machine gun, pistol, or so on you use. In fact, none of these matter. These threads don't matter, none of this does at all. But still, we post here, and here we are.

With that out of the way; the majority of terminal ballistics purpose is the medical and forensic field, where we study such things to treat gunshot wound victims better, and to better understand just how projectiles (and indeed, their effects on the human body ) operate. The study and science of projectile trauma leads to significantly better treatment and care of patients who have been shot, and this does not just include in a hospital setting.

With this in mind, I suppose, if you are a writer, this might help you to add an element if the realistic to your writing. It might make you better appreciate how deadly an object, not even one third as thick as your pinky, really can be. It might make you better understand small arms and their history. Or it might just be a fun read, you can now sound smart in front of your friends.



So, how, then, do projectiles kill?

The cause of death from a gunshot wound is loss of brain function. Projectiles achieve this by stemming flow of oxygenated blood to the brain, lowering blood pressure and starving the brain of oxygen, thus killing the target. The other method is simply to sufficiently damage or destroy the brain and/or central nervous system, so as to incapacitate the target; no need to starve the brain of oxygen then, as it is already dead or unable to relay signals.

Traumatic Brain Injuries (TBIs) commonly occur with shots to the head; a TBI occurs when a sudden traumatic force causes damage to the brain. TBI can result when the skull suddenly and violently strikes/is struck by an object, or when an object pierces the skull and enters brain tissue. These cause severe hematomas (ruptured blood vessels) or contusions (bruised brain tissue) within the brain, and have a high lethality rate; approximately 35% of patients who suffer TBIs and die receive them from gunshot wounds; 90% of TBIs inflicted by gunshot wounds are lethal, and the majority of patients never make it to the Emergency Room. For those who do survive the initial trauma, half never make it to the operating table. The primary method by which TBIs kill is blood loss; normally caused by destruction of tissue and severance of vital blood vessels, or by transfer of projectile energy through the brain in the form of a shockwave, thereby sufficiently damaging the brain as to degrade function and cause hemorrhaging.

In wounding, there are several major methods by which the projectile imparts its effects upon the target. Every method relies upon the continued travel of the projectile to a minimum rate of penetration. Commonly, this is defined as 300mm/12 inches of ten-percent ballistics gelatin, a substance that closely mimics the properties of soft tissues in animals and humans. It is important to note that ballistics gelatin, while an excellent approximation, does not mirror the density of the human body perfectly, as it does not model skin nor bone. It is, however, an excellent approximation short of actually shooting, say, a cadaver. This figure is considered the “minimum” to reach and damage important organs in the body; the US Military utilizes a different gelatine, 20-percent, and specifies 250mm/10in as the minimum.

All figures we discuss shall be represented as being ballistics gel.

During the bullets travel through the striking medium, a number of things may occur to create a more effective wound.

The projectile may travel straight through without anything occurring besides its travel. This method has no particular name besides travel. No longer a particularly normal method of wounding, this method creates a relatively normal wound cavity, with little noteworthy performance. This type of wound is highly dependent on the caliber of the bullet, and its velocity; Larger, faster bullets will be far more effective at creating large wound cavities than their smaller counterparts, thereby being more lethal*.

During its travel, the projectile may expand and deform, creating a larger surface area. Similar to above, this projectile relies upon momentum and penetration to create a large wound cavity. These are designed to expand via hydraulic pressure when striking medium, thereby increasing their size and surface area. Commonly, these are hollow point of soft point bullets. As the projectile increases in surface area, so does the resistance on the bullet, which can (and does) limit the penetration of the projectile. However, the larger surface area can create a very large permanent and temporary wound channel; bullets of the hollow-point nature are known to expand at sizes in excess of 20% of their original size, while soft-ponts expand less, but tend to penetrate more. Speaking purely in terminal ballistics, a handgun is generally more effective with hollow point ammunition, a rifle is generally better with soft point ammunition.

Military ammunition, today, generally uses neither of these methods in full, for a myriad of reasons. The principal reason for this is generally that full metal jacket (FMJ) ammunition is in use with pretty much all militaries in the world today, and as such can not take advantage of the principals of expansion, and utilizes more efficient methods of wounding than pure travel.

FMJ offers a number of advantages over its non-FMJ brethren ballistically, being more aerodynamically efficient, retaining ability better, and offering superior penetration of medium. While a number of international laws regulate militaries to using only FMJ ammunition with a non-open, non-concave meplat (The tip of a bullet), I am of the belief that military ammunition eventually would have realized the benefits of FMJ ammunition over other ammunition as body armor became more and more prevalent and we would have arrived at FMJ ammunition as standard eventually.

Some modern military ammunition relies of a principal called yaw. The principal of yawing is quite simple: The penetrating projectile begins to flip nose-to-end, thereby constantly increasing (and decreasing) the volume of the wound. This method may use deformation to accomplish this, where the projectile deforms upon impact to create more lift/downforce on a segment of the projectile, creating the tumbling effect. These projectiles typically penetrate very well, while also creating very large wound channels. This creates an exceptionally large wound channel, which can damage a large number of organ tissues in large amount, and create a very sudden drop in blood pressure (and a large one at that). This method is generally very effective and constant regardless of factors imparted on the projectile; though there are instances in which the bullet fails to yaw.

Other ammunitions may fragment. These ammunition types break apart upon impact with medium and create a number of sub-projectiles that travel through medium. As they travel, they generate a large number number of wound channels than an individual projectile, but, as they lose mass and therefore momentum, they often fail to perforate tissues in significant amount. These wound channels are typically massive in size, but not as long as their yawing counterparts. However, they normally meet and exceed the minimum requirements for penetration, and are are generally considered to be on par with their yawing counterparts.

So, how does modern military ammunition do it?


However they want. They all use, to some degree, all of these methods in order to obtain maximum potential of lethality.

One of the most famous members of this family is the AK-74 series rifles 5.45x39mm cartridge. Some call it “The poison bullet”, and make many allegations as to its lethality. I have heard everything from “They call it that because the Soviets would cover it in fecal matter!” to “The wound kills you days later and you didnt even know it”.

None of these are true in the least. 5.45x39mm is not undeserving of the name “The poison bullet”. It is, arguably, the standard for modern military ammunition lethality. A small caliber, high-velocity projectile, it develops a wound profile far outside what was, prior to its introduction, believed to be capable of conventional full-metal jacket ammunition. How, then, did Soviet designers create such a bullet?

The 5.45x39mm was the result of an experiment that had been ongoing since the late 1950s to develop a small caliber, high-velocity projectile. Many believe 5.45x39mm was developed as an immediate response to the United States adoption of 5.56x45mm; this was not the case. The 5.45x39 was certianly influenced by 5.56x45mms adoption; however, the Soviet Union has been experimenting with the concept for about the same time the United States had.

Testing had indicated the 5mm calibers wound cavity was “undesirable”, being far smaller than then in-service 7.62x39mms; designers solved this problem with a very simple solution.

The projectile utilizes a hollow nose cavity at the immediate front of the projectile, and a center of gravity behind the geometric median point. The hollow nose causes the nose of 5.45x39mm to deform into an “L” shape, creating a surface in which more drag is applied to, causing a destabilization of the projectile in the medium. The rearward center of gravity promotes rotation of the projectile, causing a massive amount of yaw.

The results are massive. 5.45x39 is the ballisticians delight of a projectile, with a long bullet, a high muzzle velocity and excellent characteristics, it is considered by many to be one of the best cartridges ever put into service.

The more Western 5.56x45mm NATO has utilized a number of methods in its service life, and through a number of variants, to achieve the ideal wounding profile. The wounds 5.56x45mm creates are excellent, and it does so via two methods: Fragmentation and yaw. 5.56s Fragmentation occurs ideally at given velocities and distances from the muzzle of the firearm, each dependent on twistrate, barrel length, and so on. For the most part, one can expect fragmentation for a significant portion of typical engagement ranges.

Fragmentation occurs when the striking projectile is acted upon by significant hydraulic force, causing the projectile to deform and break apart. This has more to do with the construction and velocity of the projectile than most anything else; the slower the projectile is going, the less likely it will be to have sufficient force imparted upon its design to deform and fragment. This essentially means fragmentation may be considered unreliable in some ways.

When the projectile does fragment, however, the result is extraordinary. Fragments of various size and shape spread out into their own separate wound channels, causing a large area of crush cavity. Ideally, at least 40% of these fragments, as a measure of the weight of the projectile, should penetrate at least 12 inches/30cm of tissue, with about 16in/40cm being a fairly average penetration distance.


With these methods explained, I can answer a question I was asked.


What Criteria should a projectile meet for a military projectile to be considered terminally effective?

Excellent question. Actually, this is a question that has plagued military ballistics experts for years; at what point is a projectile no longer considered satisfactory in terms of terminal performance?

It is very rare for this question to actually be answered in a cohesive fashion.

The FBI offers a mandate of 12 inches/30cm of penetration of 10% Gel of penetration, but this is not necessarily reflective of the actual wounding capacity of a projectile. The penetration standard as set forth is a recommendation to reliably penetrate human tissue to the point where the projectile will reliably damage organ systems. However, this does not actually reflect how effective a projectile is; it merely advises it can penetrate reliably.

In truth, the penetration is just one of several values associated with the actual line of effectiveness in any projectile. These factors all accumulate to form one of the more reliable metrics for indicating projectile effectiveness: Wound cavity volume.

The wound cavity is the permanent displacement of tissue in the body as a result of the travel of the penetrating projectile. The value associated with this may be used as part of the overall determining factor in actually measuring how effective a projectile is.

There are formulas in my field for calculating the volume wound cavities during theoretical perforation of tissue. They are extremely long and complicated, very tricky to understand, and may not actually yield the correct numbers unless you understand very well what to actually use for measure in given projectiles.

Essentially, one must ascertain the volume of tissue displacement as a result of the projectiles travel. This is difficult and tricky to do, and genuinely creates a large issue for most military planners and designers; You can't actually do so, because nothing is consistent. You may get a range of data for wound volumes from 67cm³ to 145cm³, all because a stiff wind was blowing in the opposite direction.

Because it is so actually complicated to ascertain the dimensions of a wound channel for most people, it is therefore a difficult to answer question. However, I can attempt to quantify it.

Penetration should meet the 12 inch/30cm penetration minimum, and exceed it. Ideally, a 16 inch/40cm penetration should be met, and the wound cavity should not be less than 5.0 Cubic Inches/82cm³ overall. The projectile should attempt to fragment or yaw during its travel, thereby increasing surface area and increasing likelihood the projectile has struck vital areas. This cavitational size is sufficient to allow for rapid loss of blood and will cause incapacitation rapidly enough in a target.

The best way to accomplish this is to simply use a proper sized projectile with a sufficient design to perforate tissue effectively. This means that things like microcalibers (Calibers smaller than 5mm in diameter) are likely not desirable, unless designed in such a way to efficiently cause yaw or fragmentation at a constant rate and in sufficient amount. This means, therefore, one would need to create a projectile of a long caliber to produce increased wounding effects during deformation and destabilization.

You might, too, want to upscale; it may seem like a good idea, then, to move your standard cartridge to larger caliber for the purpose of superseding the minimum. This is problematic from an infantry standpoint due to the inherent weight increase you get with rifles, magazine, and new ammunitions in these new calibers. This is why, generally most modern militaries stick with calibers of the 5mm diameter area; they offer the ideal size, power, and weight ratio for modern militaries and automatic rifle fire.



You might wonder how to engineer a good bullet for the purpose of making a terminally effective round. Dont worry. Its shockingly easy to do so.

For the purpose of military ammunition, one should endeavor to use a Full Metal Jacket projectile with a spitzer nose in really any era after 1910. The projectiles are more aerodynamically efficient, and more terminally efficient than their predecessors. Spitzer projectiles are inherently unstable when traveling through medium due the the tapering shape of the projectile, which creates a slightly rearward center of gravity. This means the nose of the projectile has more lift, which causes yaw. To improve upon this, one should attempt to make the nose of a projectile several calibers in length; normally about 2-2.5 calibers in length is a comfortable medium.

A sectional density of greater than .16 is highly desirable; it ensures the projectile will be able to overcome resistance in travel, allowing for a good penetration rate. This generally means a heavier bullet for a given diameter, which is the result of the materials the bullet is made of. This is more complex and will take some learning to understand, learning outside the scope that this post attempts to encapsulate.

A bullet following these parameters, being of sufficient mass and material construction, when fired at a sufficient velocity, will be able to penetrate the minimum required tissue and create a wound channel properly.

This concludes my general overview of terminal ballistics and introduction to wounding effects. An expansion of any section may be requested and more advanced questions can be answered at request. If any sections need clarifications, please feel free to ask.

Nothing better than a little lite reading.

[Nirvash Type TheEND]

This concludes my general overview of terminal ballistics and introduction to wounding effects. An expansion of any section may be requested and more advanced questions can be answered at request. If any sections need clarifications, please feel free to ask.

A good post.

What.

Did you post in the wrong thread? It's not even about swords and no one will read it.

I'm starting to think all this sword backlash is discriminatory. Check your fucking privilege.

[The Archangel Conglomerate]

This concludes my general overview of terminal ballistics and introduction to wounding effects. An expansion of any section may be requested and more advanced questions can be answered at request. If any sections need clarifications, please feel free to ask.[/spoiler]

An extremely enlightening and informative post, Puz. I truly appreciate the time and effort you put into making this.

[Crookfur]

What rifle am I most likely to find in the hands of penal companies that fire upon my military?

The same one as the rest of the army firing at you...

[Imperial isa]

Is the EMERK rifle mix of M16 and SA80 after a one night stand ?

[Husseinarti]

Is the EMERK rifle mix of M16 and SA80 after a one night stand ?

It's the only way to make the SA80 any good.

[Nirvash Type TheEND]

Lizzie's gonna need a skin graft after that one.

[Husseinarti]

Lizzie's gonna need a skin graft after that one.

The SA80 isn't alone in its shitness.

It has the G36 and the FAMAS friends.

Friends in being shit.