The 6.8 mm Remington Special Purpose Cartridge (aka 6.8 SPC, 6.8 SPC II & 6.8×43mm) is a rifle cartridge that was developed by Remington Arms in collaboration with members of the U.S. Army Marksmanship Unit, United States Special Operations Command to possibly replace the 5.56 NATO cartridge in a Short Barreled Rifle(SBR)/Carbine. Based upon the .30 Remington cartridge,[5] it is midway between the 5.56×45mm NATO and 7.62×51mm NATO in bore diameter and muzzle energy. It uses a 7.0 millimetres (0.277 in) (7.0358 mm) diameter bullet, the same as that used in the venerable .270 Winchester hunting cartridge. It is particularly adaptable to current 5.56 mm NATO firearms, sharing the same cartridge overall length of 57.4 millimetres (2.260 in).
The 6.8 mm Remington Special Purpose Cartridge (aka 6.8 SPC, 6.8 SPC II & 6.8×43mm) is a rifle cartridge that was developed by Remington Arms in collaboration with members of the U.S. Army Marksmanship Unit, United States Special Operations Command to possibly replace the 5.56 NATO cartridge in a Short Barreled Rifle(SBR)/Carbine. Based upon the .30 Remington cartridge,[5] it is midway between the 5.56×45mm NATO and 7.62×51mm NATO in bore diameter and muzzle energy. It uses a 7.0 millimetres (0.277 in) (7.0358 mm) diameter bullet, the same as that used in the venerable .270 Winchester hunting cartridge. It is particularly adaptable to current 5.56 mm NATO firearms, sharing the same cartridge overall length of 57.4 millimetres (2.260 in).
In tests, it was determined that a 6.5mm barrel had the best accuracy, but a 7mm barrel had the best terminal performance. Further tests showed that a 6.8mm barrel was the best compromise between the two, providing accuracy, reliability and terminal performance up to 500 meters. The combination of the cartridge case, powder load, and projectile easily outperformed the 7.62x39mm Soviet cartridge, with the new cartridge proving to be about 61 m/s (200 ft/s) faster. The resulting cartridge was named the 6.8 Remington Special Purpose Cartridge due to the size of its barrels and the fact that it was based on the .30 Remington case.
