The M16 initially proved unpopular with American military personnel; while the weapon was far lighter in weight than the standard issue rifles used previously, early versions suffered from internal corrosion and extraction jams. However, problems were quickly corrected and over time the rifle's reputation dramatically improved. Over the years since, numerous variant models of the weapon have been produced, including several carbine variants.
Notably, the M16's STANAG 30-round magazine was adopted as standard across the majority of NATO nations, with all new standard issue rifles being designed to accept it. This allowed units in the field to exchange ammunition and magazines quickly and effortlessly at the individual soldier level, regardless of which nation's service they belonged to. The M1913 Picatinny rail accessory mounting system, pioneered on the M4 carbine, was later similarly adopted by NATO members on their own weapons.
In Aliens, M16A1s were used as set dressing in the armory aboard the USS Sulaco, seen stored on racks in the background. Parts from the M16 were also used as the basis for the M240 Incinerator Unit, most notably the receiver and carry handle.
In Predator 2, Mike Harrigan armed himself with a compact AR-15 variant before his final confrontation with the City Hunter (the weapon is never seen clearly enough to correctly identify the model). The carbine he uses is fitted with an underslung M203 grenade launcher. Earlier in the film, LAPD officers are seen with M16A1s at the scene of the subway massacre.
- Several of the M16s seen in Predator, including those carried by Dutch and Billy, are not actually M16s, but rather civilian-legal semi-automatic-only AR-15 Sporter-1 (SP1) rifles that have been dressed up with M16A2 furniture and converted to fully-automatic. These weapons were used extensively in action movies of the 80s and 90s as it was easier to acquire and convert an SP1 than it was to obtain a real, military-issue M16. The same rifle used by Dutch in Predator was used in the 1983 film Scarface by Al Pacino's character Tony Montana.
- In Aliens: Colonial Marines the Sulaco appears to have been raided as the M16A1s and L85A1s seen in Aliens are notably absent. However this could likely just be a graphical oversight.