The M16 rifle (officially designated Rifle, Caliber 5.56 mm, M16) is a family of assault rifles adapted from the
In … See more

In 1928, a U.S. Army 'Caliber Board' conducted firing tests at Aberdeen Proving Ground and recommended transitioning to smaller caliber rounds, mentioning, in particular .27 in (6.86 mm) caliber. Largely in deferenc… See more

During the early part of its service, the M16 had a reputation for poor reliability and a malfunction rate of two per 1000 rounds fired. The M16's action works by passing high-pressure propellant gasses, tapped from the ba… See more

In March 1970, the U.S. recommended that all NATO forces adopt the 5.56×45mm cartridge. This shift represented a change in the philosophy of the military's long-held position about caliber size. By the mid 1970s, oth… See more

This was the first M16 variant adopted operationally, originally by the U.S. Air Force. It was equipped with triangular handguards, buttstocks without a compartment for the storage of a cleaning kit, a three … See more

In Vietnam, some soldiers were issued a carbine version of the M16 named XM177. The XM177 had a shorter 10 in (254 mm) barrel and a telescoping stock, which made it substantially more compact. It also possessed … See more