M240 7.62mm Machine Gun (2024)

Though initially adopted into service as a co-axial weapon for armored vehicles, the M240 family has expanded to include numerous subvariants for a wide range of applications from co-axial and pintle mountings on armored fighting vehicles, watercraft, and helicopters, to infantry versions. The US Army also developed a specialized lightweight version for infantry use.

The basic M240 is designed as coaxial machine gun for tanks and 7.62mm fire power on light armored vehicles. A companion model, the M240C, was also developed. The M240C differs from the M240 only in the feed tray and feed cover, allowing to feed from the right instead of the left on the standard M240. The M240C was developed specifically for the M2 and M3 Bradley Fighting Vehicles. M240s can be converted to M240Cs, and vice versa, but exchanging the feed tray and feed cover components. The weapons are equivalent to the FN MAG-58 for co-axial applications, itself available in both right and left hand feeds. The weapons have a rate of fire of 650-950 rounds per minute.

The M240B, originally designated as the M240E4, is a very reliable, fully-automatic, gas-operated, belt-fed, crew-served weapon. The M240B is fitted with a hydraulic buffer, which slows the cyclic rate of fire from 650-950 rounds per minute to 600-650 rounds per minute. At over 50,000 MRBF (mean rounds between failure) the M240B is widely accepted as the most reliable machine gun in the world. The M240B provides the accurate and effective sustained rate of fire required to suppress and destroy enemy soft targets. The M240B is the US Army's infantry version, equipped with a folding bipod, pintle mount, forestock and accessory rails to mount optics and target illuminators. The pintle mount allows tripod and vehicle mounting. The weapon is designed as a tripod mounted or bipod supported machine gun for use by ground forces. The bipod is integrated into the receiver assembly of the weapon.

The M240G, used by the US Marine Corps, is similar to the M240B and is intended to fill a similar role. The M240G is modified for ground use by the installation of what is referred to as an "infantry modification kit" or "egress package," comprised of a flash suppressor, front sight, carrying handle for the barrel, a buttstock, infantry length pistol grip, bipod, and rear sight assembly. The M240G is essentially the basic M240 fitted with this kit, and differs from the US Army's M240B most obviously in the lack of a heatshield and accessory rails. The M240G also features the original buffer assembly, allowing for the higher rate of fire.

The M240E1 is designed with front and rear sights, uses 7.62mm ammunition, and spade grip trigger device and is pintle mounted on light armored vehicles. It is otherwise similar to the standard M240. The M240D is a left hand feed, gas operated, air cooled, fixed head space 7.62mm weapon designed with front and rear sights and spade grip trigger for helicopter applications. Though intended primarily for mounting on aircraft, the M240D has 2 possible configurations: aircraft and egress. In the aircraft configuration the M240D has a front and rear sight and a trigger group, which accommodates the spade grip device. The ground configuration involves the installation of an egress package, which is designed to provide downed aircrew personnel with increased fire power. The egress package contains a buttstock assembly, a buffer assembly, a bipod assembly, and a conventional trigger assembly. The M240D is issued for aircraft configuration. The barrel assembly contains a 3 position gas plug. The first gas plug position allows the weapon to cycle at 750 rounds per minute. The 2 remaining ports increase the rate of fire by 100 rounds per minute each, that is to say that the second position provides a rate of fire of 850 rounds per minute, while the third position provides a rate of fire of 950 rounds per minute. The aircraft configured M240D weighs 25.6 pounds and is 42.3 inches long. The egress configuration weighs 26.2 pounds and is 49.0 inches long. The M240H, originally designated as the M240E5, is an updated version of the M240D machine gun. The M240H provides additional rail accessory points, a new flash hider, and other product improvements over the previous M240D.

The M240L, originally designated M240E6, incorporates titanium construction and alternative manufacturing methods for fabricating major M240B components to achieve significant weight savings. These improvements reduce the soldier's combat load while allowing easier handling and movement of the weapon without compromising performance. The M240L short barrel variant is 21.8 pounds, 5.4 pounds lighter than the M240B.

The M240N is designed with front and rear sights, and configured specifically for mounting on water craft. It is similar to the M240G, but lacks the integral bipod. It also uses the hydraulic buffer of the M240B, and features the lower cyclic rate of fire.