Iron .31 bow-leg mould with sprue cutter, for Hartford manufactured Colt Model 1855 Root percussion revolver. Bow-leg mould, stamped “COLT’S PATENT” with an apostrophe, on the top face of the sprue-cutter, close to the hinge. The two cavities are for a round ball nearest the hinge pin and a conical with a heel grease groove below it. The groove helps facilitate loading into the cylinder chamber. The locating pin is on the right leg. An inspectors letter “n” is stamped on the sprue cutter under “COLT’S PATENT”. The finish is blue. Rapley M#25d Overall very good condition.