The light heavy machine gun LW50MG, developed by General Dynamics, is a development of the American XM-307 ACSW / XM-312 program, which has recently experienced financial difficulties. In fact, the LW50MG machine gun became a simplified and cheaper version of the XM-312 machine gun, having lost the ability to change the caliber, the direction of the tape feed and received simplified sighting devices. This machine gun is currently being tested in the US Army, and current plans call for it to enter service in 2011. According to the same plans, the LW50MG light machine guns will have to complement the significantly heavier Browning M2HB machine guns of the same caliber in the mobile units of the US Armed Forces: airborne troops, mountain forces and special forces.
A distinctive feature of the new machine gun, in addition to its low weight, the American testers call a very high firing accuracy, which makes it possible to effectively engage relatively small targets at ranges of up to 2,000 meters. Thanks to this, the new machine gun will be able to become, among other things, an effective means of dealing with enemy snipers or individual shooters hiding behind more or less light obstacles.
The LW50MG heavy machine gun is a belt-fed, air-cooled automatic weapon. The barrel of the machine gun is quick-changeable. Automation works according to the gas outlet scheme, the barrel is locked by turning the bolt. In this case, the barrel, with the bolt box and the gas outlet assembly mounted on it, can move inside the machine gun body, forming a movable automation group. The movement of the movable group is limited by a special damper and a return spring. Food is carried out using a standard loose metal tape with any cartridges of 12.7 × 99 mm caliber, tape feed only from left to right.
The machine gun fires from an open bolt, single shots or bursts. Before firing, the bolt is inside the bolt carrier in the rear position, compressing the return-mainspring, and the entire movable group is also in the rear position, compressing its return spring. At the moment of the shot, the mobile group is released and begins to move forward, at the same time the shutter is released from the sear, picks up the cartridge and sends it into the barrel. After locking the barrel, the actual shot occurs, while the movable group (barrel coupled to the bolt, bolt box, gas outlet) continues to move forward, so that a significant part of the recoil goes to damping the impulse of the massive elements of the weapon moving forward. Under the influence of the remaining recoil impulse, the entire movable system moves backward, while under the action of the gas vent mechanism, the bolt unlocks the barrel, extracts and discards the spent cartridge case, and stands on the sear. In the case of a single fire, the entire mobile system, upon reaching the rearmost position, stops, and in case of fire in bursts, it begins a cycle of forward movement under the action of the return spring, while a special self-timer releases the shutter from the sear for the next shot. In combination with a powerful muzzle brake, this design provides a relatively low recoil, which makes it possible to make both the weapon itself and its machine fairly light. The payment for this relief, as indicated above, was a decrease in the rate of fire.
The fire controls of the LW50MG machine gun include twin vertical grips on the butt pad and a trigger between them. The machine gun can be equipped with various optical sights mounted on the Picatinny rail. Shooting is carried out from a special lightweight tripod machine or from equipment.
