Colt ACR

Colt's Manufacturing Company · Assault Rifle · Prototype · 1989

Also known as: M16A2E1, Colt Advanced Combat Rifle

Overview

The Colt ACR is an experimental assault rifle that served as Colt's entry in the United States Army's Advanced Combat Rifle (ACR) program of the late 1980s, an effort to find a successor capable of doubling the first-hit probability of the M16A2. Built on a modified M16A2 platform, it fired a duplex cartridge containing two stacked 5.56mm projectiles to increase hit probability at close range, and added an oil/spring hydraulic buffer that cut felt recoil by roughly 40 percent, a telescoping buttstock, a muzzle brake/compensator, and optics compatibility. The duplex round degraded long-range accuracy, so users still had to carry conventional M855 ball ammunition. None of the ACR contenders met the Army's requirements and the program was cancelled around 1990.

Specifications

Weight (empty)3310 g (116.8 oz)
Weight (loaded)4670 g (164.7 oz)
Overall Length1031 mm (40.59")
Folded Length932 mm (36.69")
Barrel Length518 mm (20.39")
Action TypeGas Operated
Firing MechanismHammer Fired
Trigger TypeSingle Action
Magazine Capacity30 rounds
Magazine TypeDetachable Box
Muzzle Velocity948 m/s (3110 fps)
Effective Range325 m (355 yd)
Maximum Range548 m (599 yd)
Rate of Fire650 rpm
Barrel RiflingRight Hand
Rifling Twist178 mm (7.01")
Number of Grooves6
Frame MaterialAluminum Alloy
Barrel MaterialSteel
Stock MaterialPolymer
FinishPhosphate

Calibers

Features

Service history

Operators

Production

Production years: 1988-1990

Small number of prototypes built for the Phase III ACR trials; never mass-produced.

Origin

Country of origin: United States

Designer: Colt's Manufacturing Company

Discontinued: 1990

Notes

Designated M16A2E1 internally. The duplex round used two steel-cored copper-jacketed .224-inch projectiles (roughly 2.3 g front and 2.1 g rear) loaded nose-to-tail in a standard-length 5.56x45mm case. The rifle could also fire standard M855 5.56x45mm NATO ball.

Background

The Advanced Combat Rifle program sought a 100 percent improvement in hit probability over the M16A2. Four contractors reached Phase III (Colt, AAI, Steyr, and Heckler & Koch), but none of the radical approaches (duplex rounds, flechettes, caseless ammunition) proved worth the cost, and the program ended without a winner.