expanding bullet

Drawings from 1870 of a hollow point express rifle bullet before firing (1, 2) and after recovery from the game animal (3, 4, 5), showing expansion and fragmentation Leg wound by an expanding bullet

Expanding bullets, also known as dumdum bullets, are projectiles designed to expand on impact. This causes the bullet to increase in diameter, to combat over-penetration and produce a larger wound, thus dealing more damage to a living target. For this reason, they are used for hunting and by police departments, but are generally prohibited for use in war under international humanitarian law. Two typical designs are the hollow-point bullet and the soft-point bullet.