The FN Mag (also known as the 'FN MAG 58') is a 7.62x51mm general-purpose machine gun, designed in 1952 and still used by armies across the world today. The name stands for 'Mitrailleuse d'Appui General', which is French for 'Machinegun for general applications', or 'general purpose machingun'. And indeed this is what the MAG was designed for; to be a jack of all trades, capable of being carried by individual soldiers and used to assault buildings, or to provide covering fire for an assault, or to be fitted to a vehicle for use against other vehicles.

It is gas-operated and has a variable cyclic rate, ranging from 650-1,1000rpm, depending on the setting of the gas regulator. The MAG has a quick-change barrel and an integral bipod, although there are a variety of configurations available. Whilst America opted for the M60 as a man-portable light machinegun, the MAG nonetheless found its way into the gun ports of the M60 and M1 tanks (in which capacity it is called the M240.

The MAG has been in service with the British Army since 1967, in which service it was called the GPMG, for 'General Purpose Machine Gun' - a literal bunch, the people who name military equipment. Soldiers in the field (and the ditch, the hedgerow and the forest) renamed it the 'Gimpy'.

Whilst extremely reliable and powerful it has one drawback; both the gun and the ammunition are very heavy, especially in comparison with the 5.56mm M249 SAW, which has since replaced it in most operations. Nonetheless, the MAG is still in front-line service with the British and American armies.