The M556-62 is a 5.56×45 NATO tactical cartridge loaded with a 62-grain projectile built around a tungsten-carbide penetrator and copper jacket. It is specified as an armor-piercing style round with a relatively high muzzle velocity (manufacturer lists ~3,380 ft/s) and a fairly favorable ballistic coefficient (G1 ˜ 0.298), making it intended for long-range penetration and tactical applications where improved hard-target performance is required. Handling and storage should follow standard ammunition safety practices; this round is not a general-purpose hunting or training FMJ and is designed specifically for enhanced penetration. EMG 5.56mm x 45 62 GR/4.0 API M556-62