Machine gun

A machine gun (MG) is a fully automatic and rifledfirearm designed for sustained direct fire. Automatic firearms of 20 mm (0.79 in) caliber or more are usually classified as autocannons rather than machine guns.

As a class of military kinetic projectile weapons, machine guns are designed to be mainly used as infantry support weapons and generally used when attached to a bipod or tripod, a fixed mount or a heavy weapons platform for stability against recoil. Many machine guns also use belt feeding and open bolt operation, features not normally found on other infantry firearms.