Both the U.S. Army and the U.S. Marines use the M240 machine gun— but in very different ways

First introduced in 1884, the Maxim gun changed warfare by becoming the world’s first true automatic machine gun. Its arrival marked a major shift in battlefield tactics, and the decades that followed saw rapid advances in machine-gun design. New models emerged in a wide range of forms—from lighter weapons built for infantry maneuverability to heavier systems mounted on vehicles or defensive positions for prolonged, sustained fire.

A modern product of that long evolution is the M240 machine gun, widely respected for its durability, adaptability, and proven reliability in combat. Built on more than a century of continuous weapons development, the M240 remains a core element of U.S. military firepower and continues to serve extensively with NATO forces around the world.

Design and development of the M240

Pfc. Michael Andrade patrolling while equipped with an M240L — The M240 has saw use in a number of conflicts since the 1990s. (Photo Credit: Sgt. Julieanne Morse / U.S. Army National Guard / Wikimedia Commons / Public Domain)

Developed by Belgium’s Fabrique Nationale (FN) Herstal, the M240 was introduced to the U.S. military in 1977, initially intended for use as a tank-mounted weapon. Its proven toughness and versatility soon expanded its adoption across both the Army and Marine Corps.

Chambered for the 7.62 × 51 mm NATO cartridge, the M240 is a belt-fed, gas-operated medium machine gun that offers three selectable rates of fire, ranging from 650 to 950 rounds per minute. This flexibility enables it to adapt to a wide variety of combat scenarios with consistent effectiveness.

Outperforming earlier models such as the M73 and M219, the M240 delivers far greater reliability and a substantially higher mean rounds between stoppages. Its dependability has established it as the U.S. military’s standard medium machine gun—a role it continues to fulfill today.

Adopted by branches of the US military

US service member holding the back of an M240 while sitting down — Both the US Army and Marine Corps use the M240, but in different ways. It’s also seen use by the US Coast Guard. (Photo Credit: LIU JIN / AFP / Getty Images)

Although both the U.S. Army and the U.S. Marine Corps field the M240 machine gun, they employ different mounting systems based on their respective operational requirements. Since its introduction in 2005, the Army has used the M192 Lightweight Ground Mount, which was developed to improve mobility. Its reduced weight and simplified adjustment features make it faster to move, set up, and reposition during combat operations.

The Marine Corps instead relies on the M122A1 tripod, a modernized version of the long-used M2 tripod. The upgraded design enables one-handed operation and is capable of supporting several types of machine guns without the need for additional adapters. Although both mounting systems fulfill the same basic role, their designs reflect the distinct operational approaches of each service branch.

Use of the M240 in battle

US military service member firing an M240 while at sea — The M240 can be used on the ground via a tripod or attached to a vehicle. (Photo Credit: Smith Collection / Gado / Getty Images)

The M240 has been used by American soldiers in a number of different conflicts. The first was during the Gulf War. The weapon was also carried by infantrymen during the wars in Afghanistan and Iraq. Iraqi forces used the machine gun to fight against ISIL and ISIS.

The M240 has been carried by members of the Free Syrian Army throughout the Syrian Civil War. Units have been fitted onto technicals, which are improvised military vehicles created by fitting standard pick-up trucks or similar automobiles with military weapons, such as machine guns, anti-aircraft guns or a recoilless rifle.

Many other nations have equipped the M240

Two Ukrainian soldiers sitting in full uniform — The Ukrainian military was provided with M240s to help repel the 2022 Russian invasion. (Photo Credit: Scott Peterson / Getty Images)

Several other nations also utilize the M240. The Indonesian Army has mounted the machine gun on its Leopard 2 tanks, while Poland equips its M1A2 Abrams fleet with the weapon. Spain’s Army Airmobile Force attaches the M240 to its Chinook helicopters. In 2017, Georgia switched from Russian-made guns to the M240, and in 2021, the Joint United States Military Assistance Group supplied models to the Philippines.

The Americans and NATO have also supplied M240s to armies seeking to defend themselves. Iraq received them to support their fight against groups like the Taliban, and Ukraine has been provided an undisclosed number to support their efforts against the ongoing Russian invasion.

There are a number of variants

Two soldiers aiming the M240 — A number of variants of the M240 have been produced for those serving in the US Marine Corps. (Photo Credit: Cpl. Ryan Walker / Wikimedia Commons / Public Domain)

Since its debut, there have been many versions of the M240 developed. The M240E1 is used by the Marines to mount on the likes of the LAV-25, and the service also uses the M240B as its standard medium-sized infantry machine gun. The “B” variant is also used by the US Coast Guard.

The M240L can be more easily carried. Rather than being built from steel, it’s produced from titanium, making it 18 percent lighter than the standard model. The only drawback is that it takes longer to produce and has to have extra protections added to defend against the weather.

There’s also the Barrett 240LW machine gun, made using the M240’s specifications, but aimed toward making it significantly lighter. Arms maker Barrett was able to reduce the weight through the use of different materials and through more efficiently manufacturing the gun. A shortened version, the Barrett 240LWS, was also developed.