The FN MAG is a Belgian 7.62 mm general-purpose machine gun, designed in the early 1950s at Fabrique Nationale (FN) by Ernest Vervier. It has been used by more than 80 countries, and it has been made under licence in several countries, including Argentina, Egypt, India and the United Kingdom.
The weapon's name is an abbreviation for Mitrailleuse d'Appui Général, meaning general-purpose machine gun (GPMG). The MAG is available in three primary versions: the standard, infantry Model 60-20 machine gun, the Model 60-40 coaxial machine gun for armoured fighting vehicles and the Model 60-30 aircraft variant.
The MAG Model 60-20 is an automatic, air-cooled, gas-operated machine gun, firing belt-fed 7.62×51mm NATO from an open bolt.
The MAG uses ignited powder gases vented through a port in the barrel to propel a gas piston rod connected to the locking assembly (it uses a long-stroke piston system). The barrel breech is locked with a vertically tilting, downward locking lever mechanism that is connected to the bolt carrier through an articulated joint. The locking shoulder and camming surfaces that guide the locking lever are located at the base of the receiver. The MAG uses a series of proven design concepts from other successful firearms, for example the locking mechanism is modeled on that of the Browning M1918 (BAR) automatic rifle, and the feed and trigger mechanisms are from the WWII-era MG42 universal machine gun.