Weight, unloaded: 3.35kg
Weight, loaded: 4kg
Length: 559mm (22 inches)
Barrel length: 254mm (10 inches)
Cartridge: 12.7mm x 35mm caseless telescoping (.50 Lyran CaseLess)
Action: gas-operated, balanced automatic, closed-bolt
Rate of fire: semi-automatic, 600 rpm automatic.
Muzzle velocity: 460m/s
Muzzle energy: 2284.5 J
Effective range: 100m
Feed system: twin-single stacked, 30rnd magazine
Sights: dorsal picatinny rail.
Abstract
The LY47 ‘Stormhammer’ is a compact, large-bore, balanced-automatic, gas-operated, high-lethality, bullpup-configured submachinegun of Lyran design, developed in the second decade of the 21st Century by the Lyran Protectorate Research and Development Commission.
Background
With the promulgation, and widespread implementation, of the LY46 ‘Hellhammer’ pistol, Lyran experience with high caliber small arms ammunition grew markedly. Over time, experience with caseless small arms would, itself, grow, but the .50LCL round remains one of the most potent widely available ammunition types in the world, especially available in a hand gun.
Thus, when the absence of an in-service submachine gun was brought up as an issue, it seemed logical to produce one that would utilise Lyran experience with the .50LCL ammunition type, or near-analogues.
Coupled with experience derived from the LY21 Advanced High Lethality Assault Rifle project, the LY47 came into conceptualisation, spurred on also by the awareness of a number of global tenders for submachine guns having been lodged on the markets, most notably the Sovereign Empires Coalition’s SMG request for tender. It is not certain, at this point, whether Lyran Arms intends to submit the LY47 to fulfill this contract, but is regarded very much as a distinct possibility.
Not for the fainthearted, the LY47 is an extremely powerful submachine gun, with extensive measures to reduce the recoil load (down approximately 45%) from what you’d expect from the ammunition being fired. The LY47 was also a Lyran first, in that it was the first Lyran-designed weapon to have been designed as too light, and weight was put back on to help control the recoil. At 4kg, loaded, the LY47 is slightly heavier (though appreciably shorter) than a loaded M16A1, but possesses considerably more muzzle energy, and far more projected lethality. Given the widespread use of body armour, however, this is considered acceptable for the niche roles in which SMGs are utilised.
Construction
The Stormhammer is a derivation of technologies utilised in both the LY46 ‘Hellhammer’ pistol and LY21 AHLAR, leading to a weapon that is, in many respects, a blend of both. While superficially more similar to the LY21, both weapons have had a significant impact on the Stormhammer’s design. Unconventional in layout for a submachine gun, the weapon is not entirely without precedent, however. The bullpup layout, traditionally problematic for left-handers, has circumvented the issue by the utilisation of caseless ammunition. With the use of caseless ammunition, there is no ejection, and thus no issue with where the cartridge ejects during firing.
In the advent of misfire, the weapon can be cocked, and the faulty round ejected, and firing recommenced.
The majority of the weapon’s body is made of high-durability, impact-resistant fibreglass-reinforced polyamide. This comes in a high-grip matte finish, with a variety of colours or camouflage patterns available, though the default is a muted grey.
The working parts and majority of the gas system are tungsten primarily for its very high heat tolerance, which improves the weapon’s performance and sustained accuracy.
The barrel is cold hammer-forged steel, and is chrome lined, with a 1 in 10 rifling twist.
Internal electrics are composed of Indium Gallium Arsenide, selected despite its higher cost over silicon for its extremely high resistance to electromagnetic pulse attack. Circuitry is further protected by kraton insulation, to further improve electromagnetic resilience. Given the very-short lengths of wiring, however, this was never likely to be a problem, in any case.
Operating and feed system and recoil attenuation
The LY47 is, in most respects, a reasonable conventional closed-bolt, balanced-automatic, short-stroke gas-operated system. The weapon’s caseless nature removes the requirement for ejection of cases during normal operation, which removes the step from the operating cycle. However, should cased rounds be chambered, the rearwards movement of the bolt WILL bring the spent cartridge into line with the ejection opening, and if the appropriate calibre of barrel is chosen, the round will eject.
The cocking handle is located on the left side of the weapon, and serves to load a round into the chamber, and can also be used to eject rounds in the chamber via the ejection port on the right hand side of the weapon.
The LY47’s balanced-automatic system is based on utilisation of the propellant gases to drive not just the piston which drives the bolt rearward towards battery, but also to push a secondary piston and counterweight in the opposite direction, ie towards the muzzle. The mechanics are such that as the bolt reaches the furthest rearward part of its recoiling (thus impacting the rubber pads of the interior of the butt plate), the counterweight also reaches the end point of its forward movement. This 'balanced recoil' action noticeably decreases felt recoil and thus improves controllability and accuracy in fully automatic or rapid-semiautomatic firing. Given the high power of the .50LCL round, this balanced automatic feature is important, although not indispensable.
Borrowing from the LY20, the rubber pads described above are of further relevance if a silencer is fitted, as this padding also significantly reduces the sound produced by the bolt and piston assemblies impacting their respective stops, circumventing the tell-tale 'click-click-click' sound of silenced automatic weapons fire. It is worth noting, however, that a silencer for a .50LCL round might well be longer than the weapon that is firing it.
The 30 round magazine of the Stormhammer borrows from innovations made during the production of the LY21, and is a double-well, single-stacked magazine.
The rounds are oriented towards the muzzle of the weapon at all stages of the firing sequence. The bolt feeds first the right well, then, once the right well is empty, the magazine catch at the bottom of the well causes the bolt to rotate as it moves forward, thus feeding from the left well. Once the left well is empty, the magazine catch prevents the weapon from locking forward, which makes for a slightly faster reload time by a trained operator.
LY47 magazines are about similar in length to magazines found on most other 30-round-capable submachine guns, although are appreciably wider, both parallel and perpendicular to the bullet’s lie. Weight is quite a bit less than the bulk would suggest, with the absence of the case providing more than a little by way of weight saving, making for more comfortable carriage of ammunition than would be expected for rounds of the requisite size and power. The light-weight, high-strength, semi-transparent plastic magazine, with readily delineated notches, also provides for easy assessment of the number of remaining rounds, should the shooter lose count (an easy prospect, given the high-capacity magazines).
Recoil mitigation was a factor considered early on in the design, and lessons learned on both the LY21 and LY46 were considered. Given the high power of the .50LCL cartridge, and the fact that this is a submachine gun, not a rifle, mitigation of felt recoil is, in fact, an extremely high priority. The LY47's 254mm barrel is fitted with a high-efficiency, heavy-construction muzzle brake and recoil compensator, which vents propellant gases sideways and, notably, up, which counteracts the conventional tendency for a weapon's muzzle to rise when fired. Aesthetically similar to the muzzle brakes used on the Barret .50 AM rifles, the purpose is also not dissimilar. This muzzle-brake is internally threaded for use with silencers or sound-suppressors, and is designed to also prevent the propellant gases from kicking up dust in and around the shooter’s location, even from the basic-prone firing position. Further, the weight of the muzzle brake itself provides a partial counter to muzzle-climb during firing.
The bolt-carrier assembly moves rearwards into heavy duty recoil springs, which absorb an appreciable portion of the contact/impact with the back of the weapon.
Further, use of the patented Pachmayr-designed 'Decelerator' handgrips has been approved, following a lengthy period of discussion with the Lyran Governmental Trade Department, for use with the LY47, as they had also been on the LY46. Decelerator grips feature ergonomic finger grooves, carefully machined tactile palm grips, and a patented soft-durable rubber composite.
The use of a foregrip is encouraged, as this further helps to control the weapon during automatic firing.
The weapon’s cyclic rate of fire is relatively low, again to mitigate the effects of the very powerful .50LCL round, and, at 600rpm, is comparable to Heckler and Koch’s UMP45.
Safety system
Like all Lyran automatic-capable small arms, the Stormhammer uses a dual-pressure trigger system. Pulling the trigger to the first pressure (2.1 kg) fires semi-automatically, but pulling the trigger to the second trigger pressure (4.5kg) produces automatic fire. This system, similar to that featured on the Austrian Steyr AUG, enables the operator to employ either semi-automatic or automatic fire without adjusting the weapon in any way, or breaking the firing position. A single-shot lockout stud, located below the trigger, can be pulled out to prevent the trigger being pulled rearward to the second pressure, and thus will prevent accidental employment of automatic fire. The stud can be pushed back into the trigger, thus re-allowing automatic fire, by a split-second movement of the index or middle finger of the master hand.
Safety of the AUG, set to ‘fire’.
The LY47 borrows most of the features of its safety system from the earlier LY20 and -21. The safety is located immediately above the weapon's pistol grip, and is a simple thumb or index-finger operated push-action trigger-lock safety. The safety protrudes 1cm from the weapon's right, just above the first finger-joint of an average right-hander's index finger, when in safe mode, and displays a white dot to the operator.
When switched to “fire” condition, the safety is taken offline by the index finger pushing it into the weapon. The safety will then protrude 1cm out the opposite (left hand) side of the weapon, and display a red dot to the operator, indicating the weapon's state of readiness visually, as well as to physical inspection. This safety system, identical to that featured on the AUG, was selected for its ability to be engaged or disengaged without the operator taking his hands from the weapon's foregrip or trigger, and yet being able to check the readiness status of the weapon without visual inspection.
Ammunition
The Stormhammer uses the same .50LCL ammunition as was provided for the increasingly widespread LY46 Hellhammer pistol, and has been designed with that ammunition in mind. While more than able to handle a wide range of alternate calibres, including cased ammunition, the usage of such ammunition would obviate many of the LY47’s unique capabilities.
Caseless telescoping was originally selected when designing the LY46, and was an odd choice for use in a handgun. The logic was simple, however. Caseless telescoping ammunition was the type of ammunition for which the most propellant could be provided for a given length and width. Of further consideration is the fact that the 12.7 x 35mm cartridge is not cylindrical in cross-section, but, like the 4.7 x 33mm ammunition of the G11, is square, allowing more propellant to be packed into the cartridge's area. The caseless ammunition is used, rather than cased, to lower the weight of the charge, while allowing more of the space to be used to pack in further propellant. This same reason motivates the selection of telescoping ammunition, which provides for explosive charge packed further forward, around the point of the round.
The 12.7mm projectile is otherwise near-identical in dimensions to the .50AE, but, propelled as it is by more propellant, is over 60 metres per second faster at the muzzle of the LY46 than it is from the muzzle of the Desert Eagle. Further, the .50LCL has just shy of 2300J of energy at the muzzle, compared to the 1900J of the .50AE. By way of comparison, a conventional 5.56 x 45mm rifle round (FN SS109) has 1,767J at the muzzle of an 18 inch test barrel.
Combustible cellulose end-caps ensure that the projectile and primer sit properly within the round, and disintegrate during firing, and aid in ejection of any otherwise-faulty rounds.
.50LCL uses denatured hexogen as primary propellant, in order to dramatically reduce the ever-present threat of cook-off. In fact, the LY47 is LESS likely to cook-off than most cased rounds, with the ammunition actually having a higher heat tolerance.
The .50LCL has acquired something of a reputation for excessive power, but in many situations having too much power is far less compromising to an operation than having too little. To quote Lieutenant Colonel Parnell, of Special Forces Detachment 1, 7th Order, who was a consultant during the LY47’s design;
Is the target wearing body armour? Irrelevant. You just broke all his ribs, and may have crushed his lungs. He is out of the fight anyway, most likely.
Is he behind cover? Not anymore, no. His cover just disintegrated around him. Is this for general use? Good heavens no. But does it have a niche? I, and the rest of the development team, most certainly think so.
Sights
Dorsal picatinny rails are fitted to allow compatibility with most international standard weapon sights.
Export
The LY47 ‘Stormhammer’ is a rugged, high-power, high lethality weapon, optimized for use by niche forces of a high caliber in both training and equipment terms. Deliveries of the LY47 are made in the ‘clean’ configuration, and come with six complimentary magazines, and 180 rounds of .50LCL ammunition per weapon. The weapon sells individually at NS$1,700, and domestic production rights are available at NS $2bn.
Questions or purchases can be made through Lyran Arms
