The US Enfield M1917 is a manually operated, rotating bolt action rifle that is a near duplicate of the British Pattern 1914 (“Pattern 14”) Enfield rifle. In 1915, three private US gun manufacturers began production on the Pattern 14 at the behest of the British government, due to their inability to produce enough during World War I. When the United States entered World War I in 1917, it experienced a similar shortage of infantry rifles given that the government-operated plants were unable to produce enough Springfield M1903 rifles for US troops. Since the .303 caliber Pattern 14 rifles were already in production in the US, the US government adopted this platform and rechambered it for use with the US .30-06 round. The resulting rifle was adopted as the "US Rifle, .30 caliber, Model of 1917", and produced by the same three plants between 1917 and 1918. During that short time, more than two million M1917 rifles were produced and delivered to the US Army. There were actually more Enfield 1917’s issued during WWI than the official 1903 Springfields.
Since it never was officially adopted by the US military, during the early part of World War II the surplus M1917 rifles were shipped to Britain, where they were issued to the Home Guard.