Known for their development of the famed AR-15, Armalite’s AR-18 was another important tactical trendsetter in the black rifle space.
Evolution of the AR-18
In the early ’50s, Eugene Stoner worked on the 7.62 x 51mm AR-10 rifle, and after several years of revision, in 1956-57, the rifle was offered up as Armalite’s entry into the U.S. military’s trials to replace the M1 Garand as the standard service rifle. Stoner’s AR-10 went up against the FN FAL (dubbed the T-48 in trials) and the M-14 (dubbed the T-44) in a competition to provide the U.S. with the “rifle of the future.”
The AR-10 was not selected, so ArmaLite licked their wounds and moved on to continue designing cutting-edge firearms using state-of-the art materials (plastics, polymers, titanium and Stellite) when other manufacturers were still dealing in steel and wood.
In 1956, Stoner was also working on a new lightweight rifle, the AR-15, which fired the 5.56mm/.223 round that the U.S. and NATO were exploring. This rifle was eventually adopted by the military, beginning with the U.S. Air Force in 1961, and became the standard military rifle.
At the same time he was working on the AR-15, Stoner collaborated with ArmaLite engineer Arthur Miller on a lightweight, easy to manufacture rifle to be shopped to U.S. allies whose armed forces couldn’t afford the expensive AR-10. The AR-16 was, for all intents and purposes, an experiment. It was made of sheet metal stampings and on machinery that was not expensive and could be operated by indigenous personnel in developing nations.
The rifle was designed to have only a few machined and milled parts, including the barrel, bolt and carrier, and flash hider. Surprisingly, this rifle wasn’t intended to supplant the U.S. military’s M-14 rifles, but rather, it was designed to be a cheap and easy to manufacture rifle to support Asian, African and South American allies in the battle against communism.
Unfortunately, the rifle didn’t really make it past the prototype stage, but the lessons learned in its design and construction would be used in ArmaLite’s next automatic rifle, the AR-18.
The AR-18 was designed and patented after Stoner’s departure from ArmaLite, but it still bore some design elements from his previous AR-10, AR-15 and AR-16 offerings. Arthur Miller, who worked on the AR-16 project with Stoner, along with two other engineers named George Sullivan and Charles Dorchester, began, in 1962, to design a new AR-16.
It would be in a 5.56mm format and easy for unskilled labor to manufacture. Miller and his team took the lessons learned from the AR-16 and put them into practice with the AR-18 design. Again, it was made largely of stamped metal, and the number of forging and machining operations required for manufacture were minimized.
When the rifle debuted in 1964, it was a pretty neat offering—shorter than the AR-15, with an 18-inch barrel instead of the 20-inch AR-15. It also had a clever side-folding stock that made vehicle transport much easier than carrying a full-sized rifle. Unfortunately, by the time it was released, the U.S. was entrenched in the Vietnam Conflict and had little to no desire to adopt the new AR-18, although they did test a few. It didn’t seem like too many other nations wanted the new rifle either.
Production was started in 1967 on the rifle based on some limited orders at the Howa factory in Japan (ArmaLite at the time was more of a design and prototype company, not a manufacturing facility), and even this was problematic. The Japanese government forbade the shipment of weapons to nations actively involved in the war in Southeast Asia. As a result, production was moved to Costa Mesa, Calif.
The AR-18 had a civilian counterpart called the AR-180. This was designed to be a sporting rifle or a police long arm, and was semi-automatic only. It sold marginally well. It seemed that the only enthusiastic users of the AR-18 were those in the Irish Republican Army, which used illegally purchased and stolen ArmaLite rifles in Northern Ireland against the British, and even nicknamed the rifle “The Widowmaker.” In 1980, after roughly 16 years of production in Japan, the U.S. and, later, in Dagenham, England, production ceased.
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