The factory letter indicates the carbine was received by the warehouse on October 26, 1877, and shipped out on November 5, 1877, on order 10545. The underside of the stock behind the tang is stamped with a banner cartouches that contain the script letters "AOS". Experts believe that this cartouche was a marking applied to some of the nearly 12,000 Model 1866 carbines in 135,000-148,000 serial number range that were sold to a location in South America (possibly Argentina) in 1877. This marking is described and illustrated on page 65 of "THE WINCHESTER BOOK" by George Madis. The carbine has the distinctive brass receiver and buttplate. The barrel, magazine, barrel bands, bolt and loading gate are blued, and the hammer, trigger, and lever are color casehardened. The stock and forearm are straight grain American walnut. This carbine has the Third Model features which include less pronounced drop in the receiver profile ahead of the hammer and serial number located on the lower tang behind the trigger. The carbine has the early style front barrel band with integral front sight blade. The barrel is fitted with the second style, two-leaf rear sight. A staple-mounted saddle ring is located on the left side of the receiver. The carbine style brass buttplate has a sliding brass trapdoor compartment that contains a three-piece steel cleaning rod with brass tip. The top of the barrel is roll-stamped with the two-line legend: "WINCHESTER'S-REPEATING-ARMS. NEW HAVEN. CT./KING'S-IMPROVEMENT-PATENTED-MARCH 29. 1866. OCTOBER 16. 1860." between the lower barrel band and the rear sight. A small "S" is stamped on the top of the barrel between the rear sight and the receiver. Madis noted that this marking is seen occasionally on Model 1866 rifles and carbines in the 150,000-155,000 serial number range and appears to be an assembly or fitting mark. The serial number, "147401," is stamped in script letters on the lower tang behind the trigger. The previously discussed "AOS" banner cartouche is stamped on the underside of the stock about 2 1/4 inches below the receiver tang. There are no caliber markings on the cartridge elevator.

Very fine. The carbine is all original and retains 80% plus of the original blue. Much of the original blue finish is present on the barrel, magazine and loading gate. The blued components show traces of aged patina and have small, barely notifiable, spots of age discoloration. The barrel legend is clear. The upper and lower barrel bands have a silver-gray patina with traces of blue finish remaining in protected areas. The brass receiver and buttplate are in very good overall condition and have a good looking aged patina. The side plate joints are in perfect condition and show no sign of having been removed from the carbine. The case colors on the hammer, trigger and lever have faded to a mottled, gray-brown patina. The stock and forearm remain in very good condition with light to moderate handling wear. The right side of the forearm has a number of minor dents and scratches between the barrel band and the receiver. The stock shows a few minor handling mark with one 1/3 inch shallow dent in the lower right side slightly ahead of the buttplate. Winchester Model 1866 carbines typically the effects of hard use in a rugged environment. This carbine shows some handling wear but remains in very fine original condition.