In 1957, in an effort to increase profits from the ArmaLite venture, Fairchild decided to compete in the U.S. Army's CONARC requirement for a new six-pound, high-velocity, .22-caliber selective-fire rifle accurate to 500 yards. In response, ArmaLite engineers Gene Stoner, Jim Sullivan, and Bob Fremont used the basic AR-10 design to produce the ArmaLite AR-15 in .223 Remington, which was completed as a firing prototype in 1958. Fairchild-Armalite continued its efforts to sell both the AR-10 and AR-15 to various military forces around the world. However, the AR-10 rifle marketed by ArmaLite after 1958 was not the product-improved AR-10 developed by Artillerie Inrichtingen, but rather a design scaled-up from AR-15 plans and specifications, the AR-10a. None of the improvements incorporated by Artillerie Inrichtingen over three years of production were used in the new AR-10A.