Machine gun

Fully automatic firearm

A machine gun (MG) is a fully automatic and rifled firearm 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.

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