M4 Carbine

Colt's Manufacturing Company · Carbine · In Production · 1994

Also known as: Carbine, 5.56mm, M4, Colt Model 920

Overview

The M4 Carbine is a semi-automatic carbine chambered in 5.56x45mm NATO, produced by Colt's Manufacturing Company since 1994. Featuring a 30-round magazine capacity, this carbine offers generous firepower for duty use and home defense.

Specifications

Weight (empty)2880 g (101.6 oz)
Weight (loaded)3320 g (117.1 oz)
Overall Length838 mm (32.99")
Folded Length756 mm (29.76")
Barrel Length368 mm (14.49")
Action TypeGas Operated Direct Impingement
Firing MechanismHammer Fired
Trigger TypeSingle Stage
Trigger Pull34 N (7.6 lbf)
Magazine Capacity30 rounds
Magazine TypeDetachable Box
Muzzle Velocity905 m/s (2969 fps)
Muzzle Energy1640 J (1210 ft·lbf)
Effective Range500 m (547 yd)
Maximum Range3600 m (3937 yd)
Rate of Fire825 rpm
Barrel RiflingRight Hand
Rifling Twist178 mm (7.01")
Number of Grooves6
Frame MaterialAluminum Alloy
Barrel MaterialSteel
Stock MaterialPolymer
FinishHard Anodized

Calibers

Features

Variants

Service history

Operators

Conflicts

Production

Estimated total produced: 500,000 · Production years: 1994-present

M4/M4A1 combined production; manufactured by Colt, FN America, and Remington Defense. Over 300,000 M4s converted to M4A1 standard since 2011.

Origin

Country of origin: United States

Designer: Eugene Stoner

Notes

The M4 differs from the M4A1 primarily in its fire control group - the M4 has 3-round burst (S-1-3) while the M4A1 has full-automatic (S-1-F). Initially, only special operations units received M4A1s, while conventional forces used the burst-fire M4. Starting in 2011, the U.S. Army began converting M4s to M4A1 standard under the Product Improvement Program, with 300,000 units upgraded. The 101st Airborne Division began fielding newly built M4A1s in 2012. The weapon features a flattop receiver with Picatinny rail for mounting optics and accessories. Chrome-lined barrel and chamber provide enhanced durability. Production is now shared among multiple manufacturers including FN America, Colt, and Remington Defense.

Background

The M4 was initially issued only to special operations units and soldiers who didn't need a full-sized rifle-aircrew, tankers, and officers. It wasn't until the wars in Iraq and Afghanistan proved the value of its compact size in urban combat that the M4 became the standard-issue weapon for nearly all U.S. military personnel, replacing the full-length M16.