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The ArmaLite AR-18 is a gas-operated assault rifle chambered for 5.56×45mm NATO ammunition. The AR-18 was designed at ArmaLite in California by Arthur Miller, Eugene Stoner, George Sullivan, and Charles Dorchester in 1963 as an alternative to the ArmaLite AR-15 design, which had just been selected by the U.S. military as the M16.
While the AR-18 was never adopted as the standard service rifle of any nation, its production licence was sold to companies in Japan and the United Kingdom to police and law enforcement organizations, as well as armies and security forces of nations such as Botswana, Haiti, and Swaziland.
Many rifles found their way into the hands of paramilitary and terrorist groups, such as the Provisional Irish Republican Army (IRA) in Northern Ireland.
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