Ardavia wrote:we fight dragons, and rifles with small bullets are useful for this, as are high caliber weapons.
The smaller bullets afaik go faster, and 20mm and such do more damage.
*sigh*
There's more to "damage" then the size of the bullet. Velocity is also a chief component, as is the design of the bullet itself. "Bigger bullet = more damage" is a common misconception among people that aren't familiar with how ballistics work.
Also, larger bullets are not
inherently slower than smaller ones. Generally speaking yes, because there is less mass a smaller bullet will go faster. However, given sufficient powder charges behind it even a big bullet can go fast. This is why some .50 BMG (.50 caliber bullet, very heavy) loadings go just as fast as 5.56x45mm NATO loadings (.223 caliber bullet, lighter), and both go substantially faster then .22 Short loadings (.22 caliber bullet, extremely light). As a
general rule, bullets of the same velocity but different weights will favor the heavier bullet as having a better terminal effect, but this is only really a rule when the design of the bullets are identical and even then there are dozens of cases where this
isn't the case.
Finally, saying "20mm cartridge" is about as descriptive as saying "blue house". Yes we know that the house is blue, but how many stories is it? What's the square footage? How many bedrooms? Is it an actual house or just a trailer? 20x??? could mean
anything, from a (for example) 20x150 autocannon cartridge to a (for example) 20x30 high caliber revolver cartridge, or even a 20mm shotshell. For a real life example of just how nondescriptive the caliber is, let's look at two cartridges with the same caliber. .380 ACP is a compact pistol cartridge with a 9mm bore, designed to be fired from small, compact pistols. It is also known as 9x17 Auto, which is much more descriptive; 17mm is very, VERY small for a case, and that tells you that .380 ACP isn't going to be the hardest hitting cartridge ever. Now let's look at the other one. .357 Remington Maximum is an extremely powerful revolver cartridge with a 9mm bore. Same bore as .380 ACP, but .357 Maximum was so powerful it was considered too powerful for common revolvers and is really only used in single shot break-action rifles. It's dimensions are 9x41, which, as you can see, is over double that of the .380 ACP. Even without mentioning the fact that the .357 Maximum is overloaded as fuck and uses extremely potent powder, as well as a flat-nose bullet, you can see that the .357 Remington Maximum will perform
substantially better than the .380 ACP, even if they both have the same bullet diameter (well, in fact, the .357 has a .358 inch bullet where the .380 as a .355 inch bullet, but that 0.003 inches isn't going to be doing anything to the terminal effectiveness).