An American-designed 5.56×45mm NATO assault rifle, developed in 1957 by Eugene Stoner at ArmaLite and based on his previous AR-10 design. The rifle had initial bad notoriety due to the original design's tendency to jam with dirt or in some weather conditions and different ammunition powder types. The M16 is still regarded effective thanks to its low weight, low recoil and high accuracy. It has been the standard weapon of the US military since 1964, and has been partially replaced by the M4 Carbine.