An anti-personnel weapon is a weapon primarily used to maim or kill infantry and other personnel not behind armor, as opposed to attacking structures or vehicles, or hunting game. The development of defensive fortification and combat vehicles gave rise to weapons designed specifically to attack them, and thus a need to distinguish between those systems and ones intended to attack people. For instance, an anti-personnel landmine will explode into small and sharp splinters that tear flesh but have little effect on metal surfaces, while anti-tank mines have considerably different design, using much more explosive power to effect damage to armored fighting vehicles, or use explosively formed penetrators to punch through armor plating.
Many modern weapons systems can be employed in different roles. For example, a tank's main gun can fire armor-piercing ammunition in the anti-tank role, high-explosive ammunition in the anti-structure role and fragmentation shells in the anti-personnel role.
There are also more exotic classes of weapons, such as neutron bombs, chemicals, and biological weapons, which are only designed to attack people. As there is a greater international criticism of them, they are therefore rarely used. These are not generally referred to as anti-personnel weapons but by their own names or group terms (e.g., NBC weapons) by which they are specifically banned. Such weapons often create much collateral damage and may affect large numbers of civilians, as well as causing long spanning consequences when they are not detonated in the case of buried explosives.
Debates
A debate has arisen over whether some primarily anti-material weapons can be used as anti-personnel weapons. The Barrett M82 rifle, standardized by the U.S. military as the M107, fires a large-caliber .50 BMG round that will penetrate most commercial brick walls and concrete blocks. It is an anti-materiel rifle designated as a Special Application Sniper Rifle and designed for use against military equipment (materiel), rather than against other combatants. It is used by many armies around the world both in regular forces and in special forces units. As it uses a .50 BMG round, this has led to some debates in the U.S. armed forces about the legality of using such a large anti-materiel rifle round against a human. There have been persistent reports that some U.S. military personnel believe that the use of .50 BMG in a direct antipersonnel role is prohibited by the laws of war. However, Maj. Hays Parks states that "No treaty language exists (either generally or specifically) to support a limitation on [the use of .50 BMG] against personnel, and its widespread, longstanding use in this role suggests that such antipersonnel employment is the customary practice of nations."
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 Ammunisjonsfabrikk (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.