Colt Firearms manufactured 15,000 Thompson Submachine Guns for the Auto-Ordnance Corporation in 1921, with all 15,000 originally designated Model 1921. They had a cyclic rate of approximately 800 round per minute and were not fitted with Cutts compensators. Between 1926 and 1928, the Marine Corps obtained a few Model 1921 Thompsons, and based on their combat experience in Nicaragua and China, they recommended a reduction in the rate of fire to around 600 rounds per minute. In response to the Marines, Auto-Ordnance modified the bolt, recoil spring and pilot rod to reduce the rate of fire to a more manageable level and added a Cutts compensator to the muzzle to reduce barrel climb during automatic fire. In 1928, Auto-Ordnance redesignated/remarked the modified 1921 guns as "Model 1928". The modified Thompsons had "U.S. NAVY" stamped above the "MODEL OF 1921" marking on the left side of the receiver and "8" hand-stamped over the "1" in "1921". Although the guns were marked "U.S. NAVY", most Model 1928 Thompsons were sold to law enforcement. This gun has the larger, second style Cutts compensator with Cutts trademarks and patent markings on the top. The gun has the 1928 internal components which include: (1) a 1928 second style blued weighted actuator, (2) long one piece pilot rod. (3) small diameter recoil spring. The gun has the original finned barrel and folding leaf rear sight marked: "MADE BY 'LYMAN' MIDDLEFIELD, CONN. U.S.A." on the base. The internal components on the trigger frame and stock are finished bright. The front of the detachable stock is stamped with the small anchor symbol used by the stock-maker Remington Arms. The forearm and pistol grip appear to be original Colt/AO components. The left side of the trigger frame has the second style "FULL/AUTO", "SINGLE" and "FIRE-SAFE" markings found on most Colt/AO Model 1928 guns. In addition to the model markings and the serial number "NO 13104", the left side of the receiver is roll-stamped: "THOMPSON SUBMACHINE GUN/CALIBRE .45 AUTOMATIC COLT CARTRIDGE/MANUFACTURED BY/COLT'S PATENT FIRE ARMS MFG. CO./HARTFORD, CONN., U.S.A." in five lines below the rear sight. The right side of the receiver is roll-stamped: "AUTO-ORDNANCE CORPORATION./NEW YORK, U.S.A." in two lines followed by the six-line block of patent dates. An encircled "JHB" monogram utilized by Auto-Ordnance inspector John Barrett is lightly stamped ahead of the patent marking. The top of the receiver is roll-stamped with the distinctive Thompson "Bullet" trademark. The bottom of the trigger frame is stamped with the matching serial number "NO 13104". Included with this Thompson are: (1) one 50 round "L" WWII Auto-Ordnance drum magazine and one rare early 100 round drum magazine also marked Auto-Ordnance Corp that is serial numbered 1088 on both sides, (6) six early Colt/AO 20-round magazines, four with the early two-line 1920 and 1921 patent dates and two without, (1) one very rare 20 round magazine for the 45 ACP shot cartridges, (2) 30 round CO marked magazines, and (1) one box of rare 173 grain, 45 ACP, Remington, Metal Penetrating Ammunition. This lot also includes a very rare small metal cleaning kit and a box of very desirable spare parts, that includes a spare bolt, rate actuator, recoil spring and guide, a new (in the tube) Thompson barrel, a nickel-plated oiler, and a copy of the book "Thompson: The American Legend, The First Submachine Gun" by Hill.

Excellent with 95% plus of the original blue finish overall, edge and high spot wear, and blue loss on the compensator and the underside rear area of the trigger housing directly behind the pistol grip. The wood components are all in very fine condition showing some minor handling marks on the sides. The various accessories are all in very fine condition with the case in fine condition showing wear on the ends and corners. A really top condition late Thompson Model 1921/1928 U.S. Navy overstamp with a ton of accessories and spare parts. NOTE: This item is restricted as a National Firearms Act (NFA), fully transferable Class 3, which is registered with the Bureau of Alcohol, Tobacco, Firearms and Explosives, (BATFE) that is classified as a "Curios or Relic" as defined in 27 CFR, 478.11. These weapons are still subject to the provisions of 18 U.S.C. Chapter 44 and 27 CFR part 478.