Patent ID: 7743706

Claim:
A bullet ( 10 ) for cleaning an interior surface of a gun barrel ( 11 ), said bullet comprising: a cylindrical cartridge section ( 12 ) having an open end and an opposite end closed by a rear wall ( 18 ); said cylindrical cartridge section ( 12 ) having a diameter selected to provide that said open end of said cylindrical cartridge section ( 12 ) is enabled to telescope into a shell chamber of a gun barrel ( 11 ); a rear wall ( 18 ) enclosing a rear end of said cylindrical cartridge section ( 12 ); a cylindrical projectile section ( 20 ) having an open end telescoped through an open end of said cartridge section ( 12 ) to said rear wall ( 18 ); an explosive cake ( 16 ) positioned against said rear wall ( 18 ) and inside said open end of said projectile section ( 20 ) and said cartridge section ( 12 ); a disk ( 21 ) positioned against said cake and inside said projectile section ( 20 ) and said cartridge section ( 12 ); said disk including a pin ( 19 ); a forward wall section ( 20 A) joined to an end of said projectile section ( 20 ) opposite said rear wall ( 18 ); said cylindrical cartridge section ( 12 ), projectile section ( 20 ) and forward section ( 20 A) enclosing a chamber ( 14 ); a lubricating cleaning fluid filling said chamber ( 14 ); at least one exit port ( 13 ) formed in said forward wall a plurality of trenches circumferentially arranged on an outside surface of said projectile section ( 20 ) and forward wall ( 20 A); a plurality of brushes having bristles with one end secured to a floor of each trench ( 27 ); said bristles contacting said interior surface of said barrel when said projectile section ( 20 ) is propelled through said gun barrel after said explosive cake ( 16 ) is detonated; said forward wall ( 20 A) having an array of seams extending radially from a centerline of said forward wall, said seams defining sections of said forward wall providing that when said disk is propelled toward said forward wall, said pin and disk force said sections apart from one another along said seams and force said plurality of brushes on said forward wall into contact with said interior surface of said barrel; an interior wall bulge ( 23 ) at a location on an interior surface of said projectile section ( 20 ) where said projectile section ( 20 ) is joined to said forward wall ( 20 A); slits in an outer surface of said forward wall ( 20 A) where said forward wall ( 20 A) is joined to said projectile section ( 20 ) providing that when said cake ( 16 ) explodes and said disk encounters said interior wall bulge, an outer surface of said projectile section and said forward wall is forced to expand and force said brushes against said interior surface of said barrel.