M240B

Machine Gun, 7.62 mm, M240
A right-side view of the M240B
Type	General-purpose machine gun
Place of origin	Belgium (designed) United States (manufactured)
Service history
In service	1977–present
Used by	See Users
Wars	Gulf War Iraq War War in Afghanistan Syrian Civil War Iraqi Civil War (2014-present)
Production history
Designer	Ernest Vervier
Designed	1950s
Manufacturer	FN America,U.S. Ordnance, Barrett Firearms Manufacturing
Produced	1977–present
Variants	See Variants
Specifications
Weight	27.6 lb (12.5 kg) (M240B) 25.6 lb (11.6 kg) (M240G) 22.3 lb (10.1 kg) (M240L)
Length	49.7 in (1,260 mm)
Barrel length	24.8 in (630 mm)
Width	4.7 in (120 mm)
Height	10.4 in (260 mm)
Cartridge	7.62×51mm NATO
Action	Gas-operated, open bolt
Rate of fire	M240, M240E1, M240C, M240D and M240G: Gas Setting 1: 650–750 RPM Gas Setting 2: 750–850 RPM Gas Setting 3: 850–950 RPM M240B, M240L and M240H: 550–650 RPM Barrett 240LW and 240 LWS: 550–650 RPM
Muzzle velocity	2,800 ft/s (853 m/s)
Effective firing range	800 m (875 yd) (bipod) 1,100 m (1,203 yd) (tripod)
Maximum firing range	3,725 m (4,074 yd)
Feed system	Belt-fed:
Sights	Iron sights: front blade and folding rear leaf with aperture and notch

The M240, officially the Machine Gun, 7.62 mm, M240, is the US military designation for the FN MAG (French: Mitrailleuse d'Appui Général, English: general-purpose machine gun), a family of belt-fed, gas-operated medium machine guns that chamber the 7.62×51mm NATO cartridge.

The M240 has been used by the United States Armed Forces since the late 1970s. It is used extensively by infantry, most often in rifle companies, as well as on ground vehicles, watercraft and aircraft. Despite being heavier than some comparable weapons, it is highly regarded for reliability and its standardization among NATO members is a major advantage.

All variants are fed from disintegrating belts, and are capable of firing most types of 7.62 mm (.30 in) NATO ammunition. M240 variants can be converted to use non-disintegrating belts. There are significant differences in weight and some features among some versions which restrict interchangeability of parts. The M240s used by the US military are currently manufactured by FN America, the American subsidiary of FN Herstal.

The M240B and M240G are usually fired from an integrated bipod, a tripod, or a vehicular mount; regarding tripod use, the U.S. Army primarily uses the M192 Lightweight Ground Mount, while the U.S. Marine Corps uses the M122 tripod, a slightly updated M2 tripod.