Colt M16A2
Colt's Manufacturing Company · Assault Rifle · In Production · 1983
Also known as: Rifle, 5.56mm, M16A2, Colt Model 905, Colt Model 945
Overview
The Colt M16A2 is the most widely adopted variant of the M16 family of assault rifles, serving as the standard infantry rifle for the United States military and dozens of allied nations for over two decades. Type-classified in September 1982 and first adopted by the U.S. Marine Corps in 1983, the M16A2 introduced major improvements over the M16A1: a heavier barrel with faster 1:7 inch (178mm) rifling twist optimized for the NATO-standard SS109/M855 62-grain ammunition, an adjustable rear sight with both windage and elevation controls, a brass deflector behind the ejection port, a three-round burst mechanism replacing full-automatic fire, and strengthened round handguards. The overall length increased by 21mm due to a longer buttstock designed for larger American soldiers. The direct impingement gas system and rotating bolt action remain largely unchanged from the M16A1. The M16A2 served as the primary combat rifle through the Gulf War, Somalia, and the early stages of the War on Terror before gradually being supplemented and replaced by the shorter M4 Carbine.
Specifications
| Weight (empty) | 3400 g (119.9 oz) |
| Weight (loaded) | 3990 g (140.7 oz) |
| Overall Length | 1007 mm (39.65") |
| Barrel Length | 508 mm (20.00") |
| Height | 248 mm (9.76") |
| Width | 64 mm (2.52") |
| Sight Radius | 500 mm (19.69") |
| Action Type | Gas Operated Direct Impingement |
| Firing Mechanism | Hammer Fired |
| Trigger Type | Single Stage |
| Magazine Capacity | 30 rounds |
| Magazine Type | Detachable Box |
| Muzzle Velocity | 948 m/s (3110 fps) |
| Muzzle Energy | 1796 J (1325 ft·lbf) |
| Effective Range | 550 m (601 yd) |
| Maximum Range | 3600 m (3937 yd) |
| Rate of Fire | 800 rpm |
| Barrel Rifling | Right Hand |
| Rifling Twist | 178 mm (7.01") |
| Number of Grooves | 6 |
| Frame Material | Aluminum Alloy |
| Barrel Material | Steel |
| Stock Material | Polymer |
| Finish | Hard Anodized |
Calibers
- 5.56x45mm NATO · primary · SS109 / M855 — also known as 5.56 NATO, 5.56x45, .223 Remington
Features
- Firing modes: Semi Automatic, Burst 3
- Feed systems: Detachable Box Magazine
- Safety mechanisms: Manual Safety Selector, Half Cock Notch
- Features: Fixed Stock, Select Fire, Three Round Burst, Chrome Lined Barrel, Chrome Lined Chamber, Rotating Bolt, Direct Impingement Gas System, Adjustable Rear Sight, Case Deflector, Brass Deflector, Heavy Barrel Forward, Round Handguards, Fixed Carrying Handle, Forward Assist, Birdcage Flash Hider, Pistol Grip, Inline Stock Design, M203 Grenade Launcher Compatible
Variants
- Colt M16 (M16A1) — Predecessor
- M16A3 — Full Automatic
- Colt M16A4 — Flat Top Receiver
- M4 Carbine — Carbine
- Diemaco C7 — Canadian Variant
- Colt Canada C7A2 — Canadian Improved
Base model
Service history
Operators
- United States Marine Corps · adopted 1983 · as M16A2
- United States Army · adopted 1986 · as M16A2
- United States Air Force · adopted 1986 · as M16A2
- United States Navy · adopted 1986 · as M16A2
- Canadian Armed Forces · adopted 1984 · as C7
- Australian Defence Force · adopted 1989 · as M16A2
- Israel Defense Forces · adopted 1986 · as M16A2
- Philippine Armed Forces · adopted 1987 · as M16A2
- Royal Thai Armed Forces · adopted 1988 · as M16A2
- Colombian National Army · adopted 1990 · as M16A2
- Salvadoran Armed Forces · adopted 1990 · as M16A2
- Jordanian Armed Forces · adopted 1990 · as M16A2
- Royal Netherlands Army · adopted 1995 · as C7NLD
- Danish Home Guard · adopted 1996 · as M16A2
Conflicts
- United States invasion of Grenada (1983)
- United States invasion of Panama (1989-1990)
- Gulf War (1990-1991)
- Somali Civil War (1992-1995)
- Bosnian War (1992-1995)
- Kosovo War (1998-1999)
- War in Afghanistan (2001-2021)
- Iraq War (2003-2011)
- War on Terror (2001-present)
Production
Estimated total produced: 4,000,000 · Production years: 1982-present
Approximately 4 million M16A2 rifles produced by Colt and FN Manufacturing for US military and foreign military sales. Part of over 8 million total M16-family rifles produced.
Origin
Country of origin: United States
Designer: Eugene Stoner
Notes
The M16A2 replaced the full-automatic fire selector with a three-round burst mechanism to improve ammunition conservation and hit probability in combat. The heavier barrel profile forward of the handguards resists bending from rough handling and is slower to overheat during sustained fire, while the barrel under the handguards retained the M16A1 profile for M203 grenade launcher compatibility. The 1:7 twist rifling was specifically adopted to stabilize the longer, heavier NATO SS109/M855 62-grain bullet and the even longer M856 tracer round at 948 m/s muzzle velocity, a reduction from the M16A1's 991 m/s with the lighter M193 round. The rear sight was upgraded from the M16A1's simple L-type flip to a fully adjustable windage and elevation aperture. Production was shared between Colt and FN Herstal (FN Manufacturing). The M16A2 continues to see service with reserve and training units in the US military and remains the primary service rifle in many countries worldwide.
Background
The M16A2 was largely the brainchild of the United States Marine Corps, who drove the requirement for a heavier barrel, improved sights, and the three-round burst mechanism. The Marines adopted it a full three years before the Army in 1983. The burst mechanism was controversial from the start: unlike the M16A1's simple full-auto trigger group, the A2's burst cam does not reset between trigger pulls, meaning a shooter could get a 1 or 2-round burst instead of the expected 3 if the cam was mid-cycle from a previous pull. The Army later reverted to full-auto with the M4A1, essentially admitting the burst feature was a mistake. The M16A2's development was heavily influenced by NATO standardization efforts that led to the adoption of the Belgian SS109 cartridge as the 5.56mm NATO standard in 1980, chosen over the American M193 in competitive trials.