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General purpose machine gun


The M240 machine gun proved to be a very reliable weapon

Country of origin United States
Entered service 1977
Caliber 7.62x51 mm NATO
Weight (empty) ~ 11.8 kg
Length 1 263 mm
Barrel length 630 mm
Muzzle velocity 853 m/s
Cyclic rate of fire 750 - 950 rpm
Practical rate of fire 100 rpm
Magazine capacity Belt-fed
Sighting range 800 m
Range of effective fire 800 m
Range of effective fire (mounted on a tripod) 1 100 m


   The M240 is a US-built version of the Belgian FN MAG, that is one of the most widespread and effective General Purpose Machine Guns (GPMGs) in the world. Since its introduction in 1957 the FN MAG has dominated the market for Western Block machine guns. It was proposed for the US military. However it was originally rejected in favor of the US-made M60. Ironically 2 decades after the M60 was adopted, it was replaced by a US-built version of the MAG, designated as the M240. It was adopted by the US Army in 1977 and replaced the M73 and M219 machine guns. The M240 has also been adopted by the US Navy, Marine Corps and Coast Guard. It is also used by the Spanish Army. This weapon is manufactured in the USA by a local division of the Fabrique Nationale. Production of the M240 still continues and improved and updated variants continue to emerge. This weapon was used during various military conflicts, including the recent wars in Iraq and Afghanistan.

   The M240 is used by the infantry, and may be mounted as a fixed weapon on tripods, vehicle mounts, helicopters and watercraft.

   The M240 has several design attributes of the World War II-era German MG-42, including its trigger mechanisms, quick-change barrel, and spring-loaded dust cover. But much of the weapon was derived from the basic design formula of the venerable Browning Model 1918 BAR. In fact most of the Belgian FN MAG was created by simply inverting the BAR's receiver, so it could be belt-fed from above rather than magazine-fed from below.

   The M240 is gas-operated weapon. Barrel is above and the gas regulator. This machine gun fires from an open bolt.

   It is a selective fire weapon, but does not have a single shot capability. The fire selector switches between a rate of fire of 750 rpm, 850 rpm, or 950 rpm. However the firing rate is adjusted only when fouling causes sluggish operation of the weapon and there is no time to clean the weapon properly.

   A safety is integral to the design, which disables the sear when set to "safe", but it can only be safed when the weapon is cocked.

   Ammunition is fed into the upper left side of the weapon by a belt. The M240 accepts linked belts with disintegrating or non-disintegrating links. These belts are typically 50 to 250 rounds in length, typically in boxes or pouches. Sometimes these are attached to the weapon itself. The 50-round belts are the most widely-used, and can be linked end-to-end.

   The M240 is bulkier and heavier than contemporary machine guns. However it proved to be a very reliable weapon. Several sources report that the MAG is the most reliable machine gun in the world. For example, during testing in the 1990s, it was able to fire an astonishing 26 000 rounds between failures. This reliability was further confirmed in a 2013 torture test of the M240B, after which there was no loss of accuracy, despite the weapon firing a total of 15 000 rounds at its cyclical rate of fire. By the end of that 2013 test, it had fired more than 32 000 rounds without ill effect. The barrel is rated for 800 rounds fired before replacement, but the M240 has frequently exceeded this requirement. According to some sources this weapon have been able to fire 8 000 rounds out of individual barrels before requiring a replacement, even when the barrels were heated until they glowed red hot. Barrels with advanced lining materials have even longer life ratings, with Stellite-lined barrels claimed to last for 15 000 rounds.

   Most of the components of the M240 are interchangeable with the Belgian FN MAG and its derivatives, such as the British L7A1.

   This weapon has quick-change barrels. A carrying handle is attached directly to the top of the barrel. It allows the crew to quickly remove an expended barrel while it is still hot, with no need for insulated gloves to handle it.

   The M240 has composite buttstock, foregrip and pistol grip. Early versions of the original FN MAG had wooden furniture, while newer models also employ composite materials.

   A folding bipod is standard equipment, allowing the M240 to be fired from a stable position while resting on the ground or a raised object (such as a wall or a boulder).

   The sight is a folding leaf type, with an aperture and notch in the rear, and a simple blade in the front. The rear sight is adjustable for sighting range, from 200 m to 800 m. Newer variants have a Picatinny-type scope rail and accept optics.

   Maximum effective range of the M240 is 800 m when fired from a bipod and 1 100 m when fired from a tripod.

   Throughout the years the US M240 machine guns have been improved and upgraded by installing various upgrade kits.

   Price of this weapon is approximately US $9 500.




   M240B is an improved version, used by some US Army units. It is the standard infantry general purpose machine gun, used by the US Marine Corps (M60E4). It is also used by the US Navy (Mk.43) and Coast Guard. This weapon has a hydraulic buffer system, which reduces the felt recoil. Similar system was used on the M60 machine gun. This weapon has only one gas setting, reducing the fire rate to 650-750 rounds per minute. This feature increases reduces the stress on the mechanism and increases service life of the weapon. A side effect to that is that the M240B will not fire when extremely fouled. Currently in the US Army service the M240B is being replaced by a lighter M240L.

   M240C is a coaxial machine gun. Its trigger was replaced by the electric solenoid. It is used on the M2 and M3 Bradley fighting vehicles, LAV armored vehicles and all M1 Abrams series main battle tanks.

   M240D is a pintle-mounted version. It is an upgrade of the M240E1. Pistol grip and buttstock were replaced by the spade grips. There is also an egress package this weapon. It allows the aircrew to remove this machine gun from the downed helicopter and use it as an infantry weapon.

   M240E1 is a US Marine Corps version, used on vehicles, like the LAV-25.

   M240G was developed for the US Marine Corps. It is a version of the M240E1, designed for coaxial use on tanks and armored vehicles. It can is also used on vehicle pintle mounts. The M240G has 3 gas settings. It allows the machine gun to be fired between 650 and 950 rounds per minute. This feature allows the shooter to adjust the gas bleed of the action and continue firing when the weapon is very fouled from sustained shooting. It has a Picatinny-type rail system. This weapon can be modified for ground use by installing a special kit. The US Marine Corps converted a large number of older M240 and M240E1 machine guns to the M240G standard.

   M240H is an improved version of the M240D, fitted with a Picatinny-type scope rail on a feed cover. Also it has improved flash suppressor.

   M240L is a lighter version of the M240B. It was developed following a weight reduction program. Formerly this weapon was known as M240E6. The M240L is 2.5 kg lighter than the M240B. That's a whooping 18% reduction in weight. The M240L incorporates lightweight titanium parts and different manufacturing methods for fabrication of major components. The US Army began replacing its M240B machine guns with the M240L. However Marine Corps have not adopted this weapon yet due to its high price.

   M240P is a compact version of the M240L, with a shorter barrel and collapsible stock.














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