Raufoss Mk 211

The Raufoss Mk 211 is a .50 caliber (12.7×99mm NATO) multipurpose anti-matériel projectile produced by Nammo (Nordic Ammunition Group, a Norwegian/Finnish military industry manufacturer of ammunition), under the model name NM140 MP. It is commonly referred to as simply multipurpose or Raufoss, which refers to Nammo's original parent company: Raufoss Ammunisjonsfabrikker (Ammunition Factory) in Raufoss, Norway, established in 1896. The "Mk 211" name comes from the nomenclature "Mk 211 Mod 0" used by the U.S. military for this round.

The multipurpose name is based on the projectile having an armor-piercing (tungsten core), an explosive, and an incendiary component, thus making it capable of penetrating lightly armored targets and causing damage to personnel inside the target after penetration. It is a suitable round for engaging helicopters, aircraft and lightly armored vehicles, as well as unarmored vehicles, and it is capable of igniting jet fuel. The Mk 211 has about the same destructive power as a standard 20mm round against such targets.

The Mk 211 is a very popular .50 caliber sniper round used in the Barrett M82 rifle and other .50 BMG rifles. It is also often used in heavy machine guns such as the M2 Browning. Due to its popularity several U.S. arms manufacturers produce the round under license from NAMMO Raufoss AS. There is also a tracer variant, the MK300, used in the Browning heavy machine gun.

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