US Patent 10018455 Firearm cleaning shell

An apparatus is disclosed including a bore cleaning device configured to clean a bore of a firearm. The device includes a propellant providing a force to push the projectile down the bore of the firearm, a fibrous cup, a dense material within the fibrous cup, and a frame including a bore forward disk configured to press against a bottom surface of the fibrous cup. The dense material includes one of a dense granulated material and a dense, viscous paste. The dense material is configured to deform and press radially outwardly against the cup as the propellant provides propelling force to the dense material.