This is a well weathered frontier Colt but none the less one of the hardest conversion to acquire.  It's a all matching (including the cylinder) serial number pistol. The barrel, frame, trigger guard and back strap are serial #1633. The cylinder is serial #633.  The assembly number is 331. According, to the information gathered by Bruce McDowel in his definitive book "A study on Colt Conversions" there are less than two dozen true 12 notch conversions known. This was the result of a survey taken over a period of 30 years.  A copy of the chapter on these rare pistols will come with the pistol.. The grips are also well weathered and are worn at the toes on both sides. The action functions but occasionally needs a little help with the full rotation of the cylinder. McDowel  address' this flaw in his book as being the real reason that Colt discontinued the 12 notch cylinder and not the common held belief that it was because of the bolt wearing through every other cylinder stop.    

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