Development
Manufactured by Fabrique Nationale d'Herstal, the FN MAG was chosen by the U.S. military for different roles after large worldwide searches and competitions. The MAG is a belt-fed, gas-operated, air-cooled, crew-served, general-purpose machine gun. Its versatility is demonstrated by its ability to be fired effectively from its integral bipod, mounted on a tripod, on ground vehicles, watercraft and aircraft. It was first adopted by the U.S. Army in 1977, as a coaxial tank gun, and slowly adopted for more applications in the 1980s and 1990s. The M240 and M240E1 were adopted for use on vehicles. This led to further adoption in more uses, especially for the army and Marine Corps infantry. While possessing many of the same basic characteristics as its predecessor, the durability of the MAG system results in superior reliability when compared to the M60. The MAG actually has a more complex gas system than the M60, but gives better reliability combined with lower maintenance requirements, though this comes at greater manufacturing cost and weight. Compared to other machine guns, its rating of 26,000 mean rounds between failure (MRBF) is quite high for its weight – in the 1970s when it was first adopted it achieved about 7,000 MRBF. It is not as reliable as some very heavy older designs, but it is quite reliable for its mass.Early history: testing and adoption
The U.S. adoption of the MAG has its origins in the late 1960s and early 1970s as a project to procure a new coaxially mounted 7.62 mm machine gun for tanks to replace the M73 and M219 machine guns then being used. The 1950s-era M73 had been rather troubled, and the derivative M73E1/M219 was not much of an improvement. A number of designs of the period from various countries were considered; the final two candidates were the M60E2 and the FN MAG, which underwent comprehensive testing alongside the older M219 for comparison. Two main criteria analyzed were "mean rounds between stoppages" (MRBS, malfunctions that can be cleared within minutes) and "mean rounds between failures" (MRBF, such as a part breaking). The results for the evaluated machine guns were the following: The MAG itself underwent some improvements and the M60E2 was a specialized coaxial variant that differed from some of the other types. The qualities of the M60 variants vary considerably, such as between the M60E4 and the M60C. The clear winner was the MAG, which was designated as the M240 in 1977 after the army competition. The M240 was adopted as the U.S. Army's standard vehicle machine gun in 1977. The Marine Corps also adopted the M240 and M240E1 for use on vehicles like the2022 military solicitation
As of March 2022 the United States Army has a solicitation ongoing for a M240 machine gun 6.8×51mm conversion kit to modify the 7.62×51mm NATO-chambered M240B and M240L general-purpose machine guns to fire the 6.8×51mm ammunition.Operation
The weapon fires from the open bolt position, meaning that the bolt is held to the rear and only moves forward as it is firing a round. The firing pin is static and the bolt moves around the firing pin, circumventing any need for a hammer. A sear is used to time the internal mechanisms of the weapon to provide a consistent rate of fire, ensuring proper function and accuracy. The rate of fire may be controlled by three different gas regulator settings. The first setting allows the weapon to cycle at 650–750 rounds per minute, the second setting being 750–850 rounds per minute, and the third setting being 850–950 rounds per minute. These settings are changed by dismounting the barrel, removing the gas regulator collar and turning the gas regulator to allow more or less gas to move through the weapon system. It is generally performed only when necessary to return the gun to operation after fouling has caused sluggish operation and there is no time to properly clean the weapon. The barrels can be exchanged rapidly, thanks to a barrel release button located on the left side of the weapon. The weapon is cleared first and then the button is held down, while the barrel's carrying handle is moved from the right side of the weapon to the center, unlocking it from the receiver. At this point, the button is released and the barrel is then pulled free of the receiver and placed to the side. The new barrel is inserted into the receiver and then the carrying handle is shifted to the right, locking it into place. During prolonged firing, the barrels can become hot enough to inflict second-degree burns instantly without becoming visibly different.Variants
The manufacturer's name for the weapon is the ''MAG 58''. The M240 adheres to FN MAG-58 specifications, allowing parts to be interchanged with other standard MAG-58s. This has significant advantages in training, logistics support, tactical versatility, and joint operations. For example, a US unit with attached British troops could supply replacement parts for their GPMG L7s, and vice versa.M240, M240E1, and M240C
The M240 is adapted as a coaxial machine gun for tanks and 7.62 mm fire power on light armored vehicles. The M240 is part of the secondary armament on the U.S. Army M1 series Abrams tank, M2/M3 series Bradley Fighting Vehicle, and the U.S. Marine Corps LAV-25. The M240E1 is the U.S. Marine Corps version of the original M240 coaxial/pintle-mounted machine gun that is used on vehicles like the LAV-25. It can also be fitted with spade grips for flexible use, like the ones from the M240D. The ''M240C'' is the right-hand variant on the original coaxial (installed alongside the main weapon) M240, it is identical to the M240 except for the ammunition cover and feed tray. It has a right-handed feed for use on theM240B
The M240B (formerly called as the M240E4) is the standard infantry medium machine gun of the U.S. Marine Corps. The U.S. Navy and Coast Guard likewise utilize the weapon system, and is also still used by some units in the U.S. Army. It comes configured for ground combat with a buttstock and bipod, though it can also be mounted on tripod, ground vehicles, aircraft, aboard ships, and small boats. It is almost always referred to as the "M240 Bravo" or just "240" verbally. The M60E4 (Mk 43 as designated by the Navy) was pitted against the M240E4 (former designation of the M240B) in the Army trials during the 1990s for a new infantry medium machine gun, in a competition to replace the decades-old M60s. The M240E4 won, and was then classified as the ''M240B''. This led to 1,000 existing M240s being sent to FN for an overhaul and a special kit that modified them for use on ground (such as a stock, a rail, etc.). This led to procurement contracts in the late 1990s for the all-new M240B. However, a new feature was added, a hydraulic buffer system to reduce the felt recoil as incorporated in the M60. While the M240B had been more reliable in the tests, it was a few pounds heavier than the M60E4, which led to the development of the lighter M240L machine gun. The Army M240 converted to the M240B configuration should not be confused with the large numbers of M240/E1 converted to the M240G configuration for the Marine Corps. The main differences between the two machine-gun variations is theM240D
The M240D is an upgrade of the M240E1, primarily in the addition of an optical rail on the receiver cover. It has two possible configurations: aircraft and egress (ground). In the aircraft configuration, the M240D has a front and rear sight and a trigger group which accommodates the spade grip device, while the ground configuration involves the installation of an egress package or "infantry modification kit", which is designed to provide downed aircrew personnel with increased firepower. The egress package contains a buttstock assembly, a buffer assembly, a bipod assembly, and a conventional trigger assembly. The barrel assembly contains a three position gas regulator. The first setting allows the weapon to cycle at 650–750 rounds per minute, the second gas setting allows the weapon to cycle at 750–850 rounds per minute, and the third setting allows the weapon to cycle at 850–950 rounds per minute. The aircraft configured M240D weighs 25.6 lb (11.6 kg) and is 42.3 in (1,074.42 mm) long, whilst the egress configuration weighs 26.2 lb (11.9 kg) and is 49 in (1244.6 mm) long.M240H
The M240H (formerly designated as the M240E5) is an improvement of the M240D, the M240H features a rail-equipped feed cover, an improved flash suppressor, and has been configured so that it can be more quickly converted to infantry standard using an Egress Kit. The M240H has an overall length of 41.6 in (1056.6 mm) with a 21.7 in (551.2 mm) barrel and weighs empty, and has a cyclic rate of fire of around 550–650 rounds per minute. The M240H entered service in 2004 on U.S. Army helicopters. It is equipped with dual spade grips and thumb-activated trigger systems, and can be quickly converted for dismounted infantry use via an egress components kit that includes a bipod and conventional pistol grip trigger module.M240N
The M240N is designed with a front and rear sights, and configured specifically for mounting on watercraft. 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 of the M240B which is around 550–650 rounds per minute.M240G
The M240G allows for commonality throughout the Marine Corps whether the weapon is used in an infantry, vehicular, or airborne role. The M240G is the ground version of the original M240 or M240E1, 7.62 mm medium class weapon designed as a coaxial/M240L
The M240L (M240 Lima), formerly the M240E6 is the product of the M240B weight reduction program which reduces the weight of the existing M240B by . To achieve 18% weight savings, the M240L incorporatesDerivatives
Barrett 240LW
The Barrett 240LW (Light Weight) program has its design roots in the original U.S. Army solicitation for a lighter M240 medium machine gun in 2010. The program called for a much lighter version of the M240, while keeping the same familiar open bolt design that the machine gun is world-renowned for. This was formally known as the M240B Weight Reduction Program, or the M240E6. The results of that solicitation ended with the adoption of the M240L by the U.S. Army. By producing the receiver out of titanium, instead of steel, FN delivered a light-weight solution by trimming the weight of the M240B by 5.5 pounds, or an 18 percent weight reduction of the original machine gun, giving it an overall weight of 22.3 pounds. The Lima is in limited service with the U.S. Army. Although Barrett did not participate in the solicitation program, the company felt that it could produce an equivalent weight reduction by more efficient manufacturing methods instead of simply switching to the much more expensive titanium receiver. In addition, the company makes the point that the majority of worldwide titanium reserves are coming fromBarrett 240LWS
The Barrett 240LWS (Light Weight Short) gas operated, belt fed, open bolt, medium machine gun is a shortened variant of the 240LW program. The design concept of this variant is to produce a viable medium machine gun that would serve in a special operations capacity, where a small team of operators could maximize a medium machine gun by having it in a shorter and lighter package than its big brother, the 240LW, or the equivalent M240B. This follows in the footsteps of the Mk 48 and the M60E6 medium machine guns, also designed for the small unit role. The Mk 48 is a variant of the M249 light machine gun, scaled up to chamber 7.62×51mm NATO; it has come across some issues in its service life; it was never designed to be a general-purpose machine gun, while the M60E6 arguably came too late to make a difference in USMC and US Army general machine gun adoption, being that the M240 design was well standardized within the DoD ranks. Both offerings are more focused on Special Operations in US Service. The Barrett 240LWS features a removable and telescoping buttstock, that has six adjustable positions. It differs from the buttstock of the 240LW by being half of its size in length, and doesn't have a polymer cheek piece. There are two telescoping rods that allows the buttstock to be extended to the desired position, when depressed from the top portion. The rods have indentations on them, which lock into positional latches within the rear of the buttstock. The hydraulic buffer is permanently encased within the stock and is necessary for recoil reduction from the reciprocating movement of the bolt group. Early prototypes had steel QD sling sockets on both sides of the stock, however current production versions will have solid steel sling loops on either side of it. This is to alleviate any damage that may occur to a sling mounted on the QD socket, and the amount of stress that it could take while carrying the machine gun. It also features a Picatinny rail that is longer compared to the Picatinny rail of the M240 machine guns, and where the Barrett M107A1 rear sight can be mounted and other various optics. The design of the feed tray cover hinge has been altered to be in the shape of a hexagon, thus allowing for the feed tray cover to be able to stay open while at a 45 degree angle to the receiver, while the machine gunner is loading a belt of ammunition. The feed tray has also been altered, with two protruding spring-loaded teeth which can bend in the direction of the ammunition belt. These teeth allows the operator to securely place a belt of ammunition on the feed tray, while at an upright angle, and not have the belt slip out while closing the cover. In addition they allow the operator to be able to squeeze the front of the belt into a closed cover because the teeth only bends in the direction of the belt, and the belt will pass over them, then the teeth will click upwards, thus locking the belt in place. Another click forward, and the belt of ammunition will be in place to fire. This allows the operator to feed a belt of ammunition into his 240LWS without ever having to possibly expose his position or line of sight, by opening the feed tray cover. The position of the pistol grip and firing control group has been redesigned to make the 240LWS even shorter than the 240LW. With this, Barrett moved the entire grip forward by about four inches, to where the front of the trigger guard is at a right angle to the ejection port. By moving the fire control group forward, the overall length can be shortened because the machine gunner no longer needs a traditionally longer stock to compensate for the original position of the pistol group, towards the very rear portion of the receiver. Instead of the operator using a cheek weld on the stock, the operator can now rest his face against the actual receiver of the machine gun, it also allows the operator to have a closer fit of the weapon. But by doing this, the bolt had to be modified accordingly, because the original location of the sear is no longer there. Barrett had to move the position of the sear catch on the bolt to further down the length of it. The bolt group is still the same as the original M240 design, with the exception of the position of the sear catch. Though moving the grip forward took away the ability to connect the LWS to the standard pintle adapter from the M192 Lightweight Ground Mount, Barrett made available as part of the system a new adjustable pintle adapter that works with both made by Military Systems Group. As of July 2017, it is not yet clear if that adapter is compatible with the M192 or M122 Traverse and Elevation (T&E) mechanism. However, the primary intended use of the LWS is not to be mounted, but instead being a part of a small man team that needs the additional firepower while on a foot patrol. It still features a non-reciprocating bolt handle, a fluted quick detachable barrel and features a quick flip-up sight, a three position gas regulator similar to the M240G's gas regulator, a standard M240 muzzle compensator, quick detach titanium bipod that has three positions, and a new redesigned handguard which no longer contacts the gas tube, minimizing heat transfer to the handguard. Unlike the current M240's solution of minimizing the heat transfer, Barrett uses a free floating handguard system, where they bolted the handguard directly to the receiver of the machine gun, instead of to the gas tube assembly. The handguard also has Keymod rail sections at the 3, 6, and 9 o'clock positions, with the side sections being separated from the bottom by a gripping surface for the operator. In 2020, Geissele Automatics acquired the 240LWS's design. Barrett 240LWS 7.62 mm medium machine gun specifications: * Operation: Gas-operated (full-auto) * Feed system: NATO standard disintegrating link belt-fed * Length: 1,079.5 mm (42.5 in) with the standard barrel and 977.9 mm (38.5 in) with the short barrel * Barrel length: 582.6 mm (22.9 in) standard barrel and 480.3 mm (18.9 in) short barrel * Weight: 9.30 kg (20.5 lb) with the standard barrel and 8.96 kg (19.75 lb) with the short barrel, while unloaded * Caliber: 7.62 mm (7.62×51mm NATO) * Effective range: 1,200 meters * Tracer burnout: 800–900 meters * Cyclic rate of fire: 550–600 rounds per minuteUsers
* * * : Standard issue GPMG. * : M240 (M240C/D) used as coaxial & pintle mounted gun on Leopard 2 Main Battle Tank. * *: M240C coaxial variant mounted on the AAV7 amphibious vehicle used by the JGSDFNon-state users
* Free Syrian Army: Used in their technicals.Gallery
See also
* Third Arm Weapon Interface SystemReferences
Bibliography
* *External links