AR15M16

AR15M16 is a term used to describe rifles that trace their design to the AR-15 platform and share lineage with the U.S. military M16 family. It is not an official designation but a shorthand for the broad range of semi-automatic civilian rifles and select-fire military variants that rely on the same core design heritage and many common components.

The AR-15 originated in the 1950s as a lightweight, magazine-fed rifle designed by Eugene Stoner for ArmaLite. In 1964 Colt began fielding the M16, a military version chambered in 5.56×45mm NATO with select-fire capability, first deployed in Vietnam. Over time, civilian AR-15 variants emerged in large numbers, emphasizing modularity, customization, and semi-automatic operation. The M16 family itself evolved through several military variants, including the M16A1, M16A2 with a 3-round burst option and improvements in sights and reliability, and the M16A4 with a flat-top receiver and accessory rails.

Design and operation across the AR-15/M16 spectrum is based on a rotating locking bolt and a gas-operated system; civilian models typically use direct gas impingement, while some variants employ a gas piston system. Both families feed from detachable box magazines and chamber commonly used calibers such as 5.56×45mm NATO or .223 Remington in civilian versions.

Variants span civilian AR-15s from numerous manufacturers to military M16 models and their descendants, including the M4 carbine. Usage ranges from sport shooting and collection to service in armed forces of multiple countries, with regulatory status varying by jurisdiction. Safety, training, and local laws govern ownership and use.