7.62x51mm NATO is a rimless, bottleneck cartridge originally designed in the United States. It is nearly identical to .308 Winchester. The 149 gr M80 is the same round used by U.S. Army snipers in their M14 rifles. The round is fully jacketed and comes in a brass case. It has a muzzle velocity of 2,790 fps and produces muzzle energy of 2,575 ft/lbs.