<Tr> <Th> Effective firing range </Th> <Td> 500 yd (457 m) </Td> </Tr> <Tr> <Th> Sights </Th> <Td> Iron sights </Td> </Tr> <P> The ArmaLite AR - 15 was a select - fire, air - cooled, gas - operated, magazine - fed assault rifle manufactured in the United States between 1959 and 1964 . Designed by American gun manufacturer ArmaLite in 1956, it was based on its AR - 10 rifle . The ArmaLite AR - 15 was designed to be a lightweight assault rifle and to fire a new high - velocity, lightweight, small - caliber cartridge to allow the infantrymen to carry more ammunition . </P> <P> In 1959, ArmaLite sold its rights to the AR - 10 and AR - 15 to Colt due to financial difficulties . After modifications (most notably, the charging handle was re-located from under the carrying handle like AR - 10 to the rear of the receiver), Colt rebranded it the Colt ArmaLite AR - 15 . Colt marketed the redesigned rifle to various military services around the world and it was subsequently adopted by the U.S. military as the M16 rifle, which went into production in March 1964 . </P>

When was the ar 15 first sold to us civilians