Technology of WWI: The Machine Gun

A machine gun is a rapid-firing, rifled long-barrel autoloading firearm designed for sustained direct fire with fully powered cartridges.

Machine gun, automatic weapon of small calibre that is capable of sustained rapid fire. Most machine guns are belt-fed weapons that fire from 500 to 1,000 rounds per minute and will continue to fire as long as the trigger is held back or until the supply of ammunition is exhausted. The machine gun was developed in the late 19th century and has profoundly altered the character of modern warfare.Modern machine guns are classified into three groups. The light machine gun, also called the squad automatic weapon, is equipped with a bipod and is operated by one soldier; it usually has a box-type magazine and is chambered for the small-calibre, intermediate-power ammunition fired by the assault rifles of its military unit.The introduction of smokeless powder in the 1880s made it possible to convert the hand-cranked machine gun into a truly automatic weapon, primarily because smokeless powder’s even combustion made it possible to harness the recoil so as to work the bolt, expel the spent cartridge, and reload.The Maxim machine gun (c. 1884) was quickly followed by others—the Hotchkiss, Lewis, Browning, Madsen, Mauser, and other guns. Some of these utilized another property of the even burning of smokeless powder: small amounts of the combustion gas were diverted through a port to drive a piston or lever to open the breech as each round was fired, admitting the next round. As a result, during World War I the battlefield was from the outset dominated by the machine gun, generally belt-fed, water-cooled, and of a calibre matching that of the rifle.