Carbine, 5.56 mm, M4

Carbine, 5.56 mm, M4
An M4 with Rail Adapter System (RAS), vertical forward grip and ACOG sight
Type	Carbine, assault rifle
Place of origin	United States
Service history
In service	1994–present
Used by	See Users
Wars	War in Afghanistan (2001–present) War in Iraq (2003–2011) Colombian Armed Conflict Operation Enduring Freedom 2008 South Ossetia war
Production history
Manufacturer	Colt Defense U.S. Ordnance Remington Arms Company
Produced	1994–present
Variants	M4A1, CQBR (Mk. 18 Mod 0)
Specifications
Weight	6.36 lb (2.88 kg) empty 6.9 lb (3.1 kg) with 30 rounds
Length	33 in (840 mm) (stock extended) 29.75 in (756 mm) (stock retracted)
Barrel length	14.5 in (370 mm)
Cartridge	5.56×45mm NATO
Action	Gas-operated, rotating bolt (Direct impingement)
Rate of fire	700–950 round/min cyclic
Muzzle velocity	2970 ft/sec (884 m/sec)
Effective range	500 m for a point target and 600 m for an area target
Feed system	30 round box magazine or other STANAG magazines.
Sights	Iron or various optics

The M4 carbine is a family of firearms tracing its lineage back to earlier carbine versions of the M16 rifle, all based on the original AR-15rifle designed by Eugene Stoner and made by ArmaLite. The M4 is a shorter and lighter variant of the M16A2 assault rifle, with 80% parts commonality.

It is a gas-operated, magazine-fed, selective fire, shoulder-fired weapon with a telescoping stock. A shortened variant of the M16A2 rifle, the M4 has a 14.5 in (370 mm) barrel, allowing its user to better operate in close quarters combat. The M4 has selective fire options including semi-automatic and three-round burst (like the M16A2 and M16A4), while the M4A1 has the capability to fire fully automaticinstead of three-round burst (like the M16A1 and M16A3). The carbine is also capable of mounting an M203 grenade launcher (the M203A1 with a 9-inch barrel as opposed to the standard 12-inch barrel of the M203 used on the M16 series) as well as its successor, theM320 grenade launcher.

The M4 carbine is heavily used by the U.S military. It is slated to eventually replace the M16 rifle for most combat units in the United States Army. The winner of the Individual Carbine competition might supplement the M4 carbine in U.S. Army service. This is for the US Army only while all other services will continue to use the M4 carbine and M16 rifles.