m4a1 carbine

"M4A1" redirects here. For the World War II tank, see M4 Sherman. For the World War II rifle, see M4 Survival Rifle.

Carbine, 5.56 mm, M4
An M4A1 with SOPMOD package, including Rail Interface System (RIS), flip-up rear sight and Trijicon ACOG 4x.
Type	Assault rifle
Place of origin	United States
Service history
In service	1997–present
Used by	See Users
Wars	War in Afghanistan (2001–present), War in Iraq (2003-present), Colombian Civil War
Production history
Manufacturer	Colt Defense
Produced	1994–present
Variants	M4A1, CQBR
Specifications
Weight	5.9 lb (2.7 kg) empty 6.9 lb (3.1 kg) with 30 rounds
Length	33 in (838 mm) (stock extended) 29.8 in (757 mm) (stock retracted)
Barrel length	14.5 in (368 mm)
Cartridge	5.56x45mm NATO
Action	Gas-operated, rotating bolt
Rate of fire	700-950 round/min cyclic[1]
Muzzle velocity	2,970 ft/s (910 m/s)
Effective range	500 m (550 yd)
Feed system	30 round box magazine or other STANAG Magazines.

The M4 carbine is a family of firearms tracing its lineage back to earlier carbine versions of the M16, all based on the original AR-15 made by ArmaLite. It is a shorter and lighter version of the M16A2 assault rifle, with 80% parts commonality with the M16A2.^[2] The M4 has selective fire options including semi-automatic and three-round burst (like the M16A2), while the M4A1 has a "full auto" option in place of the three-round burst.

Contents [hide] 1 Overview 2 History and variants 2.1 M4 MWS (Modular Weapon System) 2.2 M4A1 2.3 SOPMOD Block I 2.4 SOPMOD Block II 2.5 Future replacement 3 Design 3.1 Accessories 4 Effectiveness 4.1 2007 dust test 5 Trademark issues 6 Users 7 U.S. citizen ownership 8 References 9 External links

[edit] Overview

The M4 and variants fire 5.56x45mm NATO ammunition (they can also fire .223 Remington ammunition) and are gas-operated, air-cooled, magazine-fed, selective fire firearms with a 4-position telescoping stock. Original M4 models had a flat-ended telescoping stock, but newer models are now equipped with a redesigned telescoping stock that is slightly larger with curvature at the end.^[3] The M4 is similar to much earlier compact M16 versions, such as the 1960s-era XM177 family. Some of those visual designs are obvious in both weapons, however most of the similarities are not very noticeable.

The M4 with the newer, redesigned telescoping stock

As with many carbines, the M4 is handy and more convenient to carry than a full-length rifle. The price is slightly inferior ballistic performance compared to the full-size M16, with its nearly 6" (15 cm) longer barrel. This becomes most apparent at ranges of 300 yards and beyond. Statistically, however, most small-arms engagements occur within 100 yards. This means that the M4 is very much an adequate weapon for the majority of troops. The marginal sacrifice in terminal ballistics and range, in exchange for greatly improved handling characteristics, is usually thought to be a worthwhile compromise.^{[citation needed]}
While the M4's maneuverability makes it a candidate for non-infantry troops (vehicle crews, clerks and staff officers), it also makes it ideal for close quarters battle (CQB). The M4 was developed and produced for the United States government by Colt Firearms, which had an exclusive contract to produce the M4 family of weapons through 2009;^{[citation needed]} however, a number of other manufacturers offer M4-like firearms. The M4A1, along with the M16A4, have mostly replaced the M16A2; the U.S. Air Force, for example, plans to transition completely to the M4. The M4 is also the standard rifle for U.S. Air Force Security Forces members whether at home station or deployed abroad. They maintain a yearly qualification on it.
The United States Marine Corps has ordered its officers (up to the rank of lieutenant colonel) and Staff Non-commissioned officers to carry the M4A1 carbine instead of the M9 handgun. This is in keeping with the Marine Corps motto, "Every Marine a rifleman." United States Navy corpsmen will also be issued M4A1s instead of the M9.^[4]

[edit] History and variants