Colt Fourth Model 1851 Navy percussion revolver s/n 130437/IP, circa 1862. Civil war period, civilian Colt Fourth Model 1851 Navy percussion revolver s/n 130437/IP, manufactured circa 1862. The “I” after the serial number, stands for Ivory and the “P” stands for Plated. It has a 7½ inch octagonal barrel with address: – ADDRESS COL. SAML COLT NEW-YORK U.S. AMERICA -. The barrel, loading lever, frame and cylinder were plated. The brass back-strap and trigger-guard Grips are silver-plated and complimented with what looks like, its original one-piece ivory grips. The left side of the frame is marked ‘COLTS/PATENT’. Virtually no cylinder scene visible with remnants of the cylinder pins remaining. Bore is 7/10, good. All matching numbers including the wedge. Overall in good to very good condition with good tight action.