Eugene Stoner

Lore & Background

Eugene Stoner was born in Gosport, Indiana, and moved to Long Beach, California, where he graduated from Long Beach Polytechnical High School. Unable to afford college during the Depression, he worked as a machinist for Vega Aircraft Company. During World War II, he served in the U.S. Marine Corps as an aviation ordnance armourer, gaining experience with heavy-caliber automatic weapons. After the war, he worked at Whittaker and became a design engineer, then in 1954 became chief engineer for ArmaLite, a division of Fairchild Engine & Airplane Corporation. At ArmaLite, he designed several prototype small arms, including the AR-3, AR-9, AR-11, and AR-12, but only the AR-5 survival rifle saw adoption. His most significant innovation was the Stoner bolt and carrier piston system, patented in 1956, which uses a true expanding gas system rather than conventional direct impingement. This system was first used in the AR-10, a lightweight select-fire rifle in 7.62×51mm NATO. The AR-10 was submitted to U.S. Army trials in 1956 but was rejected in favor of the T44 (M14). The design was later licensed to a Dutch firm. As a private venture by ArmaLite, Stoner's assistants Robert Fremont and Jim Sullivan scaled the AR-10 down to fire the .223 Remington cartridge, creating the AR-15. The AR-15 was later sold to Colt, which modified it for adoption as the M16 rifle.

Reader's Guide

Eugene Stoner's significance lies in his creation of the AR-15, which became the M16 rifle, the standard U.S. military service rifle for decades. His Stoner bolt and carrier piston system, a true expanding gas system, reduced moving parts and overall rifle weight while enabling straight-line recoil. This design influenced numerous later firearms, including the M4 carbine. After leaving ArmaLite in 1961, Stoner consulted for Colt and later designed the Stoner 63 Weapons System, a modular system configurable as a rifle or machine gun. He also contributed to the TRW 6425 25 mm Bushmaster autocannon, co-founded ARES Incorporated, and at Knight's Armament Company created the SR-25 sniper rifle, used by the U.S. Navy as the Mark 11 Mod 0. His work spanned from the 1950s through the 1990s, and his designs remain widely used and imitated. In 1990, he met Mikhail Kalashnikov, inventor of the AK-47, and the two became friends.

Did You Know?

• Stoner's gas system is a true expanding gas system, not a conventional direct impingement system, as stated in U.S. patent 2,951,424.
• The AR-10 was rejected by the U.S. Army in favor of the T44, which became the M14.
• Stoner co-founded ARES Incorporated in 1972 and left in 1989 after designing the Ares Light Machine Gun.
• He met Mikhail Kalashnikov on May 16, 1990, and they became friends, 'not needing an interpreter to get their thoughts across.'