This is a nice sharp example of a US martially marked Colt 3rd Model 1851 Navy Revolver with standard 7.5" octagon barrel in .36 caliber. The serial number is in the 80,000 range and was manufactured in 1857. This was part of the last batch of Model 1851 Navies purchased by the US Army prior to the beginning of the Civil War in 1861. As one would expect to find on a gov't issue Colt, there are various inspector letters on the various parts, including two nice cartouches on the grips. It also has the less commonly seen Hartford address instead of New York...which was used for a short time prior to the Civil War.
This gun has one very unusual feature about it, which concerns the grips. The grips are absolutely original and numbered to this gun BUT they are lighter in color and a slightly different shape than walnut grips made at Sam Colt's factory in Hartford, CT. This is because they were NOT made in Hartford but were instead produced at Colt's second factory in London. So how did grips from London end up on an American-made 1851? Following a very favorable reception from the British public in 1851, Sam Colt set up a factory in London which produced approximately 40,000 Colt 1851 Navy revolvers from 1853-1856. The London Colts fared well in a limited market but eventually fell short to the more powerful double action .44 caliber Adams revolver in combat during the Crimean War. With slow sales, Sam Colt closed his London factory in 1856, shipping the remaining parts to his London Colts back across the pond to America. In subsequent years, some of those parts found their way onto American-made Colts produced in Hartford. For example, have you ever seen a Colt Navy purchased by the US Navy in the 89,000-90,000 range? If you have, then you've probably noticed these tend to have large iron trigger guards just like London Colts. Well, chances are, these were just that; iron trigger guards from the London factory. There is also a run of 1849 Pocket Revolvers around the 185,000 range in 1861 that use large iron trigger guards...also refugee components returned from London. In fact, some of the highest serial number 1851 Navies were actually finished at Hartford and marketed in the United States.
That said, that is basically how this Hartford-built 3rd Model Navy revolver ended up a year after the closure of Colt's London plant sporting a beautiful pair of English style a.k.a. "Slim Jim" grips. That it ended up being purchased by the US government makes the story all the more unique as these had to pass US gov't inspection...which they obviously did! The grips not only fit perfectly to the frame and metal straps, they are serial numbered to the gun and bear two US government inspector cartouches on each side along with a sub-inspector's initial "H" on the base. Note the Colt London contours on these grips, how the panels are thinner at the base, yet more rounded and bulbous along the top where they meet the frame. The color is also lighter than American black walnut as European walnut tends to be a couple of shades lighter. The grain is also a little different.
Overall Condition Grades to NRA Antique Very Good with sharp corners and edges. The metal has aged to a smooth light brown patina with nice uncleaned mellow brass straps and trigger guard. The cylinder has 65% of its rolled cylinder scene. Safety pins are pretty good too for a military gun with four good ones and two are a bit mashed. Markings are great as well including a crisp Colt Hartford barrel address and the all-important "U.S." under the COLT'S PATENT on the left side of the frame. Screws are excellent overall. The numbers on this gun match on the barrel, frame, trigger guard, backstrap, GRIPS, cylinder pin, and loading lever. However, the wedge is a field replaced which is not numbered and the cylinder, which IS military inspected, is a couple hundred numbers off from the rest of the gun. This is a fairly common occurrence on military Colts as it was clearly swapped during its period of usage; probably from another Navy Colt that issued to the same unit over 150 years ago. The grips are in excellent condition with great wood to metal fit and nice color. Both cartouches are clear and legible with a sub-inspector's letter "H" located on the base of the grips. The mechanics on this Colt are perfect...very crisp and indexes positively with proper cylinder retention. Barrel to frame is also tight and the wedge is very snug. The bore has strong rifling that is mostly bright with some scattered pits. Good+ overall.
For a military US-marked '51 Navy, this is well above average. It shows very little holster wear and chafing wear near the muzzle from mounted or dragoon usage. Perhaps this one was used gently by an officer in the days prior to the Civil War. BTW, the pre-war years for the US Army during the latter 1850's had quite an officer's corps made up mostly of West Point graduates. Many of the Army's best officers would resign their commissions in 1861 to join the Confederacy. Who knows, perhaps this Colt was issued to a young J.E.B. Stuart, Joseph E. Johnston, or perhaps one Robert E. Lee back when they were just soldiers in the United States Army.