No Lathe Needed, No Need To Remove Barrel From Frame
Another Ron Power "trick-of-the-trade". Use to adjust barrel/cylinder gap, square the rear barrel face and eliminate high spots. Four Sizes: .540", for Ruger® Security Six®, GP-100®; S&W K; Colt Mk III, Official Police; Charter Arms; .560", for S&W L; .625", for S&W N; Ruger® Blackhawk®, Super Blackhawk®; .687", for Ruger® Redhawk®.
Big Book Catalog, Issue:70, Page:484