Top-quality, new-manufactured mil-spec 5.56 x 45mm NATO XM193 FMJ ammo ideal for training & practice. This ammunition was produced at Lake City Army Ammunition Plant to Federal Cartridge Company specs for commercial ammunition. 55 grain FMJ boattail bullet – the exact load developed for the original M16 rifle. Headstamped with Federal logo and date of manufacture, reloadeable brass cases with crimped in boxer primers. Lacquer-sealed primer and case mouth to resist moisture. For use only in rifles with chambers designed for 5.56mm x 45 ammunition.