M4 Carbine

Overview:

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, achieving 80% parts commonality with the M16A2. 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. The M4 and variants fire 5.56x45mm NATO 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. 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. 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. 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 combat (CQC), and airborne and special operations, which is the most popular usage for the weapon. It has been adopted by United States Special Operations Command (USSOCOM) and is the preferred weapon of the U.S. Army Special Forces and Navy SEALs. The M4 was developed and produced for the United States government by Colt Firearms, which has an exclusive contract to produce the M4 family of weapons through 2009; however, a number of other manufacturers offer M4-like firearms. The M4A1, along with the M16A4, has mostly replaced the M16A2; the U.S. Air Force, for example, plans to transition completely to the M4 Carbine. The M4 Carbine 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. The M4/M4A1 5.56 mm Carbine is a gas-operated, air-cooled, magazine-fed, selective fire, shoulder-fired weapon with a telescoping stock. A shortened variant of the M16A2 rifle with a 14.5 in (368 mm) barrel, the M4 provides the individual soldier operating in close quarters the capability to engage targets at extended range with accurate, lethal fire. The original M4 Carbine has semi-automatic and three-round burst fire modes, while the M4A1 has "semi" and "full auto", with no three-round burst. The M4 Carbine achieves over 80% commonality with the M16A2 rifle and was intended to replace the .45 ACP M3 submachine guns and selected M9 pistols and M16 rifle series with most Army units (this plan was thought to be changed with the development of the XM29 OICW and the XM8 carbine. However, both projects were cancelled). The M4 Carbine is also capable of mounting the 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 of rifle.

Specifications:

Type

• Assault rifle.

Place of Origin

• United States.

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.

Muzzle Velocity

• 2,900 ft/s (880 m/s).

Feed System

• 30 round box magazine.
• Other STANAG Magazines.