ルイス軽機関銃
The United Kingdom officially adopted the Lewis gun in .303 British calibre for land and aircraft use in October 1915. The weapon was generally issued to the British Army's infantry battalions on the Western Front in early 1916 as a replacement for the heavier and less mobile Vickers machine gun. The Vickers was withdrawn from the infantry for use by specialist machine-gun companies. The US Navy and Marine Corps followed in early 1917, adopting the M1917 Lewis gun (produced by the Savage Arms Co.), in .30-06 calibre.