Winchester 12 Gauge Action Proving Dummy (1)
A modern shotgun slug is a heavy lead or copper-covered lead projectile, with or without a plastic tip, that may have what appears to be rifling, but these are special cuts in the slug to let it deform when passing through a tight choke. Slugs are intended for use in a shotgun and often used for hunting large game. The first effective modern shotgun slug was introduced by Wilhelm Brenneke in 1898, and his design remains in use today. Most shotgun slugs are designed to be fired through a choked smoothbore barrel; they must be self-stabilizing in the absence of rifling.
A shotgun slug is typically far more massive than a rifle bullet. One common 30-06 bullet, for example, weighs 150 grains (10g). The lightest common 12 gauge shotgun slug is the 7/8-oz slug, which weighs approximately 383 grains (25g).