machine gun

Rapid-firing automatic gun. The Maxim (named after its inventor, US-born British engineer H S Maxim (1840–1916)) of 1884 was recoil-operated, but some later types have been gas-operated (Bren) or recoil assisted by gas (some versions of the Browning).

The forerunner of the modern machine gun was the Gatling (named after its US inventor R J Gatling (1818–1903), patented in the USA in 1862 and used in the Civil War. It had six barrels arranged about a central axis, and the breech containing the reloading, ejection, and firing mechanism was rotated by hand, shots being fired through each barrel in turn. The US Army officially adopted it in 1866 after the war. The sub-machine-gun, exploited by Chicago gangsters in the 1920s, was widely used in World War II; for instance, the Thompson, often called the Tommy gun. See small arms.