SIG Sauer MG 338 machine gun (USA)

The SIG Sauer MG 338 machine gun, which was first introduced to the public in 2017, follows the stepts of the very similar LWMMG lightweight medium machine gun, experimentally produced by General Dynamics around 2012. An interesting side note in development of SIG MG 338 is that it, apparently, was designed with the help of the same person which earlier was associated with GD LWMMG, someone D.L. Stiemke, whose name appears in relevant patents from both GD and SIG Sauer.

 

SIG Sauer MG 338 machine gun
SIG Sauer MG 338 machine gun

 

Like its predecessor, new SIG MG 338 machine gun is optimized for powerful, long range .338 Norma Magnum (8.6x63mm) ammunition. It offers effective range that is much longer than range of 7.62×51 NATO weapons and is close to noticeably heavier .50 caliver (12.7mm) heavy machine guns such as the old M2HB Browning. New gun is also quite light, weighting less than the ubiquitous 7.62mm NATO M240 / FN MAG machine gun, which this new .338 machine gun is apparently intended to partially replace. Exact tactical role of the .338 caliber machine guns is not yet clear, but as of early 2020 it was announced that USSOCOM purchased some of SIG Sauer MG 338 machine guns for testing. Assuming relatively heavy ammunition load, this weapon will probably be used on light, high mobility vehicles with option for dismounted use. Each .338NM brass-cased cartridge with 300 grain / 19.4 gram bullet weights about 40-45 gram, and SIG composite cartridge probably weights about 35 gram, plus 6-8 gram for each belt link. Combat load of 300 rounds thus would hit the scales at between 12 and 16 kilogram, less ammo bags.

 

SIG Sauer MG 338 machine gun
SIG Sauer MG 338 machine gun

 

SIG MG 338 machine gun is a full automatic, gas operated, belt fed weapon that fires from open bolt. It uses short stroke piston gas system, with piston running below the quick-detachable barrel. Gas block is provided with manual gas regulator with two settings, for normal or suppressed use. To alleviate powerful recoil of the .338NM ammunition, action (bolt group) of the gun is housed inside a long, tubular barrel extension, which is allowed to recoil inside the outer receiver, which is made from lightweight aluminum alloy. Recoil buffer is attached to the rear end of the barrel extension. Gun is fed using disintegrating belts with open loops, and ammunition is push-fed from the belt and into the barrel. Loading and unloading is achieved through a top opening feed cover. Belt feed direction can be easily set up by the operator to feed from the left or from the right. Manual safety s ambidextrous and non-reciprocating charging handle can be set up by the user on either side of the gun. Ammunition can be fed from loose belts, or from special semi-rigid ammo pouches which can be attached to the bottom of the gun. Capacity of pouches is 30, 50 or 100 rounds. Alternately, gun can be fed via flexible chute from a large capacity ammunition can, installed on the vehicle. For mounted use, SIG Sauer MG 338 machine gun features same standard interface as M240 machine guns. For dismounted use, gun features lightweight folding bipod that is attached to the gas tube. It also features adjustable, side folding shoulder stock. Gun is equipped with iron sights, and has a Picatinny rail interface on the top of receiver for installation of various day and night sights, Red Dot, Telescope, Electro-optical or IR. For special forces use SIG Sauer MG 338 machine gun can be equipped with specially designed SIG sound and flash suppressor, made from INCONEL heat-resistant alloy. Suppressor adds about 1.2 kg to the weight of the gun.