M16A2
Colt's Manufacturing Company · Assault Rifle · In Production · 1982
Also known as: Rifle, 5.56mm, M16A2, Colt Model 905
Overview
The 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 significant improvements over the M16A1, including a heavier barrel with faster 1:7 rifling twist optimized for the NATO-standard M855/SS109 ammunition, an adjustable rear sight with windage and elevation controls, a brass deflector, a three-round burst mechanism replacing full-automatic fire to improve ammunition conservation and hit probability, and strengthened furniture. The direct impingement gas system and rotating bolt action remain largely unchanged from earlier M16 variants. 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) | 3770 g (133.0 oz) |
| Weight (loaded) | 4470 g (157.7 oz) |
| Overall Length | 1006 mm (39.61") |
| Barrel Length | 508 mm (20.00") |
| 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 | 930 m/s (3051 fps) |
| Muzzle Energy | 1730 J (1276 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 · 5.56x45mm NATO — also known as 5.56mm NATO, 5.56x45mm, .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, Adjustable Rear Sight, Case Deflector, Heavy Barrel, Brass Deflector, Round Handguards
Variants
- M16A1 — Predecessor
- M16A3 — Full Automatic
- M16A4 — Flat Top Receiver
- M4 Carbine — Carbine
- Diemaco C7 — Canadian Variant
Service history
Operators
- United States Marine Corps · adopted 1983
- United States Army · adopted 1986
- United Kingdom Armed Forces · as L85A1 supplement
- Australian Defence Force
- Philippine Armed Forces
- Israel Defense Forces
- Royal Thai Armed Forces
- Colombian National Army
Conflicts
- United States invasion of Grenada (1983)
- United States invasion of Panama (1989-1990)
- Gulf War (1990-1991)
- Somali Civil War (1992-1995)
- War in Afghanistan (2001-2021)
- Iraq War (2003-2011)
Production
Estimated total produced: 8,000,000 · Production years: 1982-present
Estimated total across all M16 variants produced by Colt, FN, and other licensees; M16A2-specific production in the millions
Origin
Country of origin: United States
Designer: Eugene Stoner
Notes
The M16A2 replaced the full-automatic fire selector with a three-round burst to reduce ammunition waste and improve accuracy under stress. The heavier barrel profile resists bending and overheating during sustained fire. The 1:7 twist rifling was adopted specifically to stabilize the longer, heavier NATO SS109/M855 62-grain bullet and the even longer M856 tracer round. The rifle 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. The rifle'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.