This Colt Single Action Army was manufactured in 1937 and is accompanied by a copy of a hand-written letter from dealer Pete Harvey dated 11-23-87 that states: "Called Marty Huber at Colt Factory Colt #356019 came into Shipping Room July 16th, 1937, as a .357 Mag. No other info available". Colt introduced the .357 Magnum caliber to the Single Action Army line in 1935 around serial number 355200. Colt manufactured 525 Single Action revolvers chambered for the .357 Magnum cartridge before production ceased in 1941. The revolver has the Colt pre-war commercial blue finish on the barrel, cylinder, trigger guard and back strap. The frame and loading gate are color casehardened. The trigger and top of the hammer are blued, and the sides of the hammer are polished bright. The checkered hard rubber grips have the Rampant Colt trademark embossed in an oval at the top. The left side of the barrel is roll-stamped: "COLT SINGLE ACTION ARMY.357". The top of the barrel is roll-stamped with the one-line Hartford legend. The left side of the frame is roll-stamped with the Colt two-Line/three-date patent markings followed by the Rampant Colt trademark. The left front of the trigger guard bow is stamped with a "4" assembler's mark above the Colt triangle "VP" proof mark. The face of the cylinder is stamped with a five-pointed star that denotes the use of special grade steel. The assembly number "729" is stamped on the inside of the loading gate. The full serial number is stamped on the bottom of the frame and the right side of the back strap and trigger guard underneath the grip. "356019" is lightly scratched on the inside of both grips. All of the visible serial numbers match. The cylinder is not serial numbered. The frame retains the fouling cut-out in the top strap which was eliminated shortly after this revolver was manufactured. The revolver is complete with its original royal blue cardboard carton. The blue and white label on the end of the carton reads "5 1/2 Colt's Army S.A. Revolver 357/Rubber Blue". Colt advertising labels are stamped on the inside of the lid and the bottom of the carton. The revolver's serial number is correctly written in grease pencil on one end of the carton bottom. Provenance: The Pete Harvey Collection; The Joe Marlin Hilliard Collection