Manufactured by the American division of the Belgian company Fabrique Nationale d'Herstal,[8] the FN MAG was chosen by the U.S. military for different roles after large worldwide searches and competitions.

[8] 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.

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.

[9] 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.

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.

In the late 1990s, the Army adopted the M240B for the infantry role – they had considered the M60E4, which (though lighter and cheaper) did not offer commonality with the vehicle-borne M240, other FN MAG users within NATO, or the USMC.

A sear is used to time the internal mechanisms of the weapon to provide a consistent rate of fire, ensuring proper function and accuracy.

[2] The M240 is adapted as a coaxial machine gun for tanks and 7.62 mm fire power on light armored vehicles.

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.

The rate of fire of the M240, M240E1, and M240C can be controlled by three different gas regulator settings; The M240D is an upgrade of the M240E1, primarily in the addition of an optical rail on the receiver cover.

The M240G is the ground version of the original M240 or M240E1, 7.62 mm medium class weapon designed as a coaxial/pintle-mounted machine gun for tanks and LAVs.

Use at high settings induces added stresses on the action and results in a shorter service life of the weapon.

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, rail systems, etc.).

The smaller gas port used on the M240B slows down the rate of fire, which increases the longevity of the machine gun by reducing stresses on the action.

The goal would be a barrel that would not need to be changed, would weigh the same, but decrease heat retention, lessen warping, and eliminate cook-offs.

They are also interested in incorporating a suppressor into the barrel, rather than having to attach one, to reduce the sound of shots and make it difficult to determine where the gunner is located.

[21] To achieve 18% weight savings, the M240L incorporates titanium construction and alternative manufacturing methods for fabricating major components.

The resulting improvements reduced the soldier's combat load while allowing easier handling and movement of the weapon.

[22][23] Titanium was used to make the receiver body, front sight post, and carrying handle while maintaining steel operating system components.

[20] The Barrett 240 Light Weight Program has its design roots in the original U.S. Army solicitation for a lighter M240 medium machine gun in 2010.

[26] 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 from Russia and China.

[27] The Barrett 240LW (Light Weight) is a general-purpose machine gun capable of mounting on a bipod, tripod, aircraft, or vehicle.

[28] The Barrett 240LWS (Light Weight Short) gas operated, belt fed, open bolt, medium machine gun is a shortened variant of the 240LW.

The hydraulic buffer is permanently encased within the stock and is necessary for recoil reduction from the reciprocating movement of the bolt group.

This is to alleviate any damage that may occur to a sling that is mounted on the QD socket, and to reduce the amount of stress taken while carrying the machine gun.

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.

[29] However, the primary intended use of the LWS is not to be mounted, but instead to be part of a small team that needs additional firepower while on a foot patrol.

The shorter barrel features dimpling which reduces weight while increasing heat dissipation with no loss of strength or durability.