COLT ACR (Advanced Combat Rifle) / U.S.A.
Colt fielded their own entrant into the ACR tests with a modified M-16A2 base rifle. The layout of many of the features from the M-16A2 were held over onto the ACR. The fire control selector was still an ambidextrous version. However now the weapon was capable of semi-automatic and full-automatic bursts, gone was the 3 round burst limiter. The weapon had been modified with a muzzle brake to help reduce recoil and reduce muzzle flash. As well the weapon was designed with a unique recoil spring buffer which was said to help reduce recoil as much as 40% over the conventional M-16A2. The weapon was designed with a 3.5X scope which would later be adopted by the Canadian military (the ELCAN), it too can be used in low light conditions.
One of the more curious aspects of the design was the rail along the top of the foregrip. It was felt that this could be used to further aide in reflex shooting in situations in which instinctive firing patterns would be used.
Unlike with the previous AAI design, the Colt ACR could be fired with standard 5.56 NATO ball and or the 5.56 Duplex cartridge that had been developed between Colt and Olin. The same brass case as used on the 5.56 rounds were used for either load to help prevent any possible loading and jamming problems. With their duplex load two rounds were stacked atop each other in the shell, each could be considered to be a miniature steel slug. The whole concept behind the design was that hit probability could be increased if there were two rounds on target at the same time. This however does not mean both will strike the same impact spot, the second round due to air drag will undoubtedly hit within the same vicinity as the first. Unlike with the flechette rounds the Duplex rounds were developed to hit targets outwards of 325 meters.
Picture and information courtesy of: PIERANGELO TENDAS