An M2 machine gun surrounded by spent shell casings

The M2 .50 machine gun, nicknamed Ma Deuce by troops, is a weapon designed by John Browning just after WWI that is still in use today. It fires .50 BMG cartridges that were designed for this weapon but today find a new use in high powered sniper rifles.

The M2 is an air-cooled, belt-fed machine gun operated on the short recoil principle. In this action, the bolt and barrel are initially locked together, and recoil upon firing. After a short distance, the bolt and barrel unlock, and the bolt continues to move forward relative to the barrel. This action opens the bolt, and pulls the belt of ammunition through the weapon, readying it to fire again, all at a cyclic rate of 550 rounds per minute. This is a rate of fire not generally achieved in use, as sustained fire at that rate will quickly 'shoot out' the barrel, necessitating replacement. In practice, the weapon is used to fire short bursts, and M2s used in the ground role are capable of either single-shot or fully-automatic operation.

It started life designed to be a aircraft machine gun (a role it did fill later on) just after World War I but was also selected for the ground role and adopted by the as the Model 1921, and served in the 1920's as a ant-aircraft and anti-armor gun. In 1932 the design was updated and adopted as the M2, though doing the same jobs.

The M2 has a maximum range of almost 7 kilometers (4.2 miles), but its maximum effective range is roughly 2 kilometers (1.2 miles) when fired from a stable mount, such as a tripod or vehicle. In its ground-portable, crew-served role, the gun itself weighs in at a hefty 84 pounds (38 kg), and the assembled M3 tripod another 44 pounds (20 kg).

The M2 .50 Browning machine gun is used for various roles:

• A medium infantry support weapon.
• When doubled it is used as an anti-aircraft gun in some ships.
• Primary or secondary weapon on an armored fighting vehicle.
• Coaxial gun in some tanks.
• A primary armament in WWII-era US aircraft, and the Korean-era US F86 Sabre.

See also

• List of individual weapons of the US Armed Forces
• List of crew served weapons of the US Armed Forces

External links

• M2 .50 Caliber Machine Gun at Federation of American Scientists
• Browning M2HB & M2HQCB (USA)