The ArmaLite AR-10 is a 7.62×51mm NATO battle rifle designed by Eugene Stoner in the late 1950s and manufactured by ArmaLite (then a division of the Fairchild Aircraft Corporation). When introduced in 1956, the AR-10 used an innovative combination of a straight-line barrel/stock design with phenolic composite, a new patent-filed gas-operated bolt and carrier system and forged alloy parts resulting in a small arm significantly easier to control in automatic fire and over lighter than other infantry rifles of the day. Over its production life, the original AR-10 was built in relatively small numbers, with fewer than 10,000 rifles assembled. However, the ArmaLite AR-10 became the sole ancestor for the AR-15 Styled Rifle platform.
In 1957, the basic AR-10 design was rescaled and substantially modified by ArmaLite to accommodate the .223 Remington cartridge, and given the designation ArmaLite AR-15.
In 1959, ArmaLite sold its rights to the AR-10 and AR-15 to Colt's Manufacturing Company due to financial difficulties, and limitations in terms of manpower and production capacity. After modifications (most notably, the charging handle was re-located from under the carrying handle like AR-10 to the rear of the receiver, and a change of the caliber to 5.56x45mm NATO), the new redesigned rifle (the AR-15) was subsequently adopted by the U.S. military as the M16 rifle. Colt continued to use the AR-15 trademark for its line of semi-automatic-only rifles, which it marketed to civilian and law-enforcement customers as the Colt AR-15.
History and development ArmaLite began as a small engineering company founded by George Sullivan, the patent counsel for Lockheed Corporation, and funded by Fairchild Engine and Airplane Corporation.Pikula, pages 23-26 On October 1, 1954, the company was incorporated as the ArmaLite Corporation, becoming a subdivision of Fairchild. With its limited capital and tiny machine shop, ArmaLite was never intended to be an arms manufacturer. The company focused on producing small arms concepts and designs to be sold or licensed to other manufacturers. Sullivan leased a small machine shop in Hollywood, California,Pikula, page 25: The workshop on Santa Monica occupied only and was referred to as "George's backyard garage" by employees. hired several employees, and began work on a prototype for a lightweight survival rifle for use by downed aircrew.
While testing the prototype of the ArmaLite AR-5 survival rifle design at a local shooting range, Sullivan met Eugene Stoner, a small arms inventor, whom Sullivan hired to be ArmaLite's chief design engineer. At the time, ArmaLite Inc. was a very small organization (as late as 1956 it had only nine employees, including Stoner). With Stoner as the chief design engineer, ArmaLite quickly released a number of unique rifle concepts.Pikula, pages 30-36
The first prototypes of the 7.62 mm AR-10 emerged between 1955 and early 1956.Pikula, page 30 At the time, the United States Army was in the midst of testing several rifles to replace the obsolete M1 Garand. Springfield Armory's T44E4 and heavier T44E5 were essentially updated versions of the Garand chambered for the new 7.62 mm round, while Fabrique Nationale submitted their FN FAL as the T48.
ArmaLite's AR-10 entered the competition late, hurriedly submitting two hand-built "production" AR-10 rifles based on the fourth prototype in the fall of 1956 to the United States Army's Springfield Armory for testing.Pikula, pages 36, 38 The AR-10 prototypes (four in all) featured a straight-line stock design, rugged elevated sights, an oversized aluminumPikula, pages 38: Later changed to titanium. flash suppressor and recoil compensator, and an adjustable gas system.Pikula, pages 27-30 In the fourth and final prototype, the upper and lower receiver were hinged with the now-familiar hinge and takedown pins, and the charging handle did not reciprocate and was not attached to the bolt carrier. For a 7.62mm NATO rifle, the AR-10 prototype was incredibly lightweight at only 6.85 lb empty. Initial comments by Springfield Armory test staff were favorable, and some testers commented that the AR-10 was the best lightweight automatic rifle tested by the Armory.Pikula, pages 39-40
The rifle's aluminum/steel composite barrel (an untried prototype design specified for the tests by ArmaLite's president, George Sullivan, over Stoner's vehement objections) burst in a torture test conducted by Springfield Armory in early 1957.Pikula, page 38: The experimental composite barrels used aluminum swaged around thin rifled liners of 416 stainless steel. ArmaLite quickly replaced it with a conventional steel barrel, but the damage had been done. The final Springfield Armory report advised against the adoption of the rifle, stating that it would take "five years or more to take it through tests to adoption". While ArmaLite objected, it was clear that the AR-10, a brand-new rifle still in the prototype stage, was at a disadvantage compared to competing designs with longer development cycles, and by 1957, U.S. Army infantry forces urgently required a modern, magazine-fed infantry rifle to replace the M1. In the end, the Army chose the conventional T44, which entered production as the M14 rifle in 1957. That same year, ArmaLite completed about 50 production AR-10 rifles at its workshop for use as demonstrator models for its sales agents, including Samuel Cummings, a famous international arms dealer.Pikula, page 46 Attempts to rush completion of these fifty rifles resulted in a few units that were assembled with improperly machined barrel extensions, a defect that went unnoticed at the time. These production rifles built at ArmaLite's workshop in Hollywood would later become known as the Hollywood model.
On July 4, 1957, Fairchild ArmaLite sold a five-year manufacturing license for the AR-10 to the Dutch arms manufacturer, Artillerie Inrichtingen (A.I.). With its large factory and production facilities, A.I. could produce the ArmaLite rifle in large quantities for which Fairchild expected orders would be forthcoming.
In 1957, Cummings secured an order of 7,500 AR-10 rifles from Nicaragua, with an initial delivery of 1,000 rifles to be delivered before January 1958.Pikula, page 45 The order was contingent on a successful completion of a 7,500-round endurance test. With the AR-10 in short supply, Cummings left his personal demonstrator rifle with Nicaragua's chief military commander, General Anastasio Somoza, who personally conducted the endurance test trial. While General Somoza was firing this rifle for the trial, the bolt lug over the ejector sheared off and flew past Somoza's head. The general angrily returned Cummings' AR-10 and canceled the entire Nicaraguan order. The remaining Hollywood rifles were inspected and refitted as necessary with new parts to prevent the reoccurrence of the bolt lug failure, but the Nicaraguan order was lost for good.
A.I. officials meanwhile discovered a number of manufacturing and production issues in the Hollywood version of the AR-10, all of which had to be resolved before large-scale production could commence.Pikula, pages 46, 50 In addition to designing and building tooling for the rifle, the design had to be converted to metric dimensions and subcontractors had to be found to supply materials or manufacture component parts.Pikula, page 50 ArmaLite also continued to send A.I. product improvement requests, including an adjustable regulator, a repositioned gas tube, and a new three-prong flash suppressor. Accessories such as flash hiders, bayonet mounts, sling swivels, and sight graduations had to be designed.
Firearms historians have separated AR-10 production under the A.I. license into at least three basic identifiable versions, along with various sporting, carbine, and other experimental designs and calibers. The three main variants have been termed the Sudanese model, the Transitional, and the Portuguese model AR-10. A.I. built all of these rifles, beginning with the Sudanese model AR-10. The Sudanese version derives its name from the sale of approximately 2,500 AR-10 rifles to the government of Sudan in 1958. The Sudanese model was equipped with a very lightweight, fluted steel barrel fitted with a trim, prong-style flash suppressor, a bayonet lug, lightweight fiberglass furniture, and sight graduations in Arabic.Pikula, page 78Pikula, page 53 The Sudanese model weighed only with an empty magazine. The price, including cleaning kit and four magazines, was US $225 per rifle.Pikula, pages 50-51 All AR-10s, whether produced by ArmaLite or by A.I., used the same Stoner-designed 20-round lightweight aluminum 'waffle' magazine with pressed-in, corrugated sides, intended to be discarded in combat once emptied.Pikula, page 29: The 'waffle' (pressed-in corrugations) was designed to add additional rigidity to the light-gauge aluminum magazine body.
AR-10 production was limited, though Guatemala, Burma, Italy, Cuba, Sudan and Portugal all purchased AR-10 rifles for limited issue to their military forces.Pikula, pages 72-73Pikula, page 75 Sudanese AR-10s were employed in frequent clashes with guerrilla forces and conflicts with neighboring countries, and a few captured rifles eventually turned up in unofficial service with various African and colonial armies, police, and guerrilla forces.Pikula, page 81 The AR-10 remained in service with Sudanese Special Forces until 1985.
In 1958, a special 7.62×39mm caliber variant of the Sudanese AR-10 was produced in very small numbers for evaluation by Finland and Germany.Pikula, page 55 That same year, an AR-10 with a 16" barrel was developed in response to a request by KLM Airlines for a carbine that could be issued to their crew for transpolar flights as part of an Arctic survival kit, and approximately 30 carbines were eventually produced. A number of Transitional AR-10s were also fitted with a folding bipod designed to lie flat under the forearm.Pikula, page 74
The Italian Navy acquired the AR-10 for its COMSUBIN underwater commando teams. Germany, Austria, the Netherlands, Finland, and South Africa also purchased small numbers of the AR-10 for test purposes, and Cuba's Batista government ordered 100 "Transitional" model rifles in 1958. The Cuban order was delivered to Havana, but in December 1958 Fidel Castro's forces took control of the country, including the warehouse containing the AR-10 shipment. In 1959, in response to a letter from ArmaLite's sales agent Sam Cummings, Castro invited Cummings to Havana to discuss payment for the AR-10 rifles. Fidel, his brother Raúl, and Che Guevara test-fired the AR-10 outside Havana. Impressed by the weapon's firepower,Pikula, page 73: Castro told Cummings he "would have been out of the Sierra Maestra two years earlier if he had enough of them." Castro paid Cummings for all 100 rifles.
However, rapidly worsening relations with the United States eliminated any chance of future AR-10 sales to Cuba, and Castro transferred the ex-Batista AR-10s to a group of Communist revolutionaries from the Dominican Republic. In June 1959, the rebels, led by Cuban officers, invaded the Dominican Republic. New York The invaders were defeated by the Dominican Army, and AR-10 rifles from the Batista shipment were found on the bodies of guerrillas.