12.7×99mm Armor-Piercing

The 12.7x99mm AP, also known as the .50 Browning Machine Gun round. It is a cartridge that first entered service in the early 20th Century. The round is based on a greatly scaled-up .30-06 cartridge. The cartridge itself has been made in many variants: multiple generations of regular ball, tracer, armor piercing, incendiary, and saboted sub-caliber rounds. The rounds intended for machine guns are linked using metallic links.

A wide variety of ammunition is available, and the availability of match-grade ammunition has increased the usefulness of .50 caliber rifles by allowing more accurate fire than lower quality rounds.

The M41-Light Anti-Aircraft Gun utilizes the 12.7x99mm Armor Piercing Rounds. The round is not to be confused with the 12.7x40mm .50 caliber semi-armor-piercing high-explosive rounds that are used with the M6 Series pistol.