The M16 rifle is the select-fire version of the AR-15 and was first built in 1959 for the U.S. Military. It uses a gas piston action via a rotating bolt. It is chambered in 5.56x45mm.
- The M16A1 appears as Cherry's/Doc's primary weapon in Conflict: Vietnam. It is incorrectly portrayed as limited to 3-round burst, while the real M16A1 is fully-automatic.
- The M16A2 with M203 grenade launcher appears as John Bradley's primary weapon in Conflict: Desert Storm and its direct sequel.
- The M16A3 is a modified version of the M16A2 adopted in small numbers by the U.S. Navy SEAL, Seabee, and Security units. It features the M16A1 trigger group providing "safe," "semi-automatic." and "fully automatic" modes instead of the A2's "safe," "semi-automatic," and "burst."
- The M16A4 is the fourth generation of the M16 series. It is equipped with a removable carrying handle and a full length quad Picatinny rail for mounting optics and other ancillary devices. The M16A4, using safe/semi/burst selective fire, became standard issue for the U.S. Marine Corps and is the current issue to Marine Corps recruits in both MCRD San Diego and MCRD Parris Island. Military issue rifles are also equipped with a Knight's Armament Company M5 RAS hand guard, allowing vertical grips, lasers, tactical lights, and other accessories to be attached, coining the designation M16A4 MWS (or Modular Weapon System) in U.S. Army field manuals.
Conflict: Desert Storm
The M16A2, called "Colt M16A2 Assault Rifle" in-game, is the main weapon used by Bradly and equipped with an underbarrel M203 grenade launcher and features semi-auto, 3-round burst, and incorrectly full-auto fire modes. It can be also seen held by American soldiers in the training missions. Another variant of the M16A2, incorrectly labeled as submachine gun and called "M16 Colt Silenced Sub-machine Gun", is the second main weapon used by Bradley and is equipped with a suppressor and an unusable scope, also incorrectly features a 32-round magazine.