Abstract: A two part projectile having a nose piece or slug (1) and a tail piece or jacket (6). The slug (1) is lead alloy and includes a cylindrical shank (3) at its trailing end. The jacket (6) has a cylindrical bore which fits over, and is permanently attached to, the shank (3). The jacket (6) is of plastics material which insulates the lead slug (1) from the heat of the burning propellent and slides easily along the bore of the gun without leaving deposits. The jacket (6) remains fixed to the slug (1) during the entire flight of the projectile.