M4 carbine
The M4 carbine (officially Carbine, Caliber 5.56 mm, M4) is a 5.56×45mm NATO, gas-operated, magazine-fed carbine developed in the United States during the 1980s. It is a shortened version of the M16A2 assault rifle.
| Carbine, Caliber 5.56 mm, M4 | |
|---|---|
| Type | Assault rifle Carbine |
| Place of origin | United States |
| Service history | |
| In service | 1994–present |
| Used by | See Users |
| Wars | See Conflicts |
| Production history | |
| Designed | 1982–1993 |
| Manufacturer | |
| Unit cost | $700 (avg. cost) |
| Produced | 1987–present |
| No. built | 500,000 |
| Variants | See Variants |
| Specifications | |
| Mass | 6.43 lb (2.92 kg) empty 7.75 lb (3.52 kg) with 30 rounds loaded magazine and sling |
| Length | 33 in (838 mm) (stock extended) 29.75 in (756 mm) (stock retracted) |
| Barrel length | 14.5 in (368 mm) |
| Cartridge | 5.56×45mm NATO |
| Caliber | 5.56 mm (.223 in) |
| Action | Gas-operated, closed rotating bolt, Stoner expanding gas |
| Rate of fire | 700–970 rounds/min cyclic |
| Muzzle velocity | 2,970 ft/s (910 m/s) (M855A1 round) 2,887 ft/s (880 m/s) (M855 round) 2,986 ft/s (910 m/s) (M193 round) |
| Effective firing range | 500 m (550 yd) (individual/point targets) 600 m (660 yd) (area targets) |
| Maximum firing range | 3,600 m (3,900 yd) |
| Feed system | 30-round detachable STANAG magazine |
| Sights | Iron sights or various optics |
The M4 is extensively used by the United States Armed Forces, with decisions to largely replace the M16 rifle in United States Army (starting 2010) and United States Marine Corps (USMC) (starting 2016) combat units as the primary infantry weapon and service rifle. The M4 has been adopted by over 60 countries worldwide, and has been described as "one of the defining firearms of the 21st century".
Since its adoption in 1994, the M4 has undergone over 90 modifications to improve the weapon's ergonomics and modularity, including: the M4A1, which strengthened the barrel and replaced the burst-fire option with fully automatic option; the SOPMOD, an accessory kit containing optical attachments; and the underbarrel weapons such as M203 and M320 grenade launchers to the Masterkey and M26-MASS shotguns.
In April 2022, the U.S. Army selected the XM7 rifle, a variant of SIG MCX Spear, as the winner of the Next Generation Squad Weapon Program to replace the M16/M4.