First revolver Colt manufactured especially for a metallic cartridge. It was not a conversion. Frame, 7.5" or 8" round barrel and 6-shot cylinder were produced for .44 rimfire metallic cartridge. Grip frame and some internal parts were taken from 1860 Army and 1851 Navy. Although this model was not commercially successful and not accepted by U.S. Ordinance Department, it did pave the way for Single-Action Army that came out shortly thereafter, and was an immediate success. Model is all blued, with case colored hammer. There are some with silver-plated brass grip frames, but most are blued steel. One-piece grips are of varnished walnut. Cylinder is roll-engraved with naval battle scene. Barrel stamped "Address Col. Saml. Colt New-York U.S. America". Later production revolvers are barrel stamped "Colt's Pt. F.A. Mfg. Co. Hartford, Ct. U.S.A." First 1,000 revolvers were stamped "Colt's/Patent". After that, 1871 and 1872 patent dates appeared on the frame. There were 7,000 revolvers manufactured in 1872 and 1873.