This exceptional Winchester Model 1866 carbine was manufactured c. 1867. This carbine has the distinctive First Model "Flatside" brass receiver which lacks the flare at the junction with the forearm, has the same receiver drop in front of the hammer as the Henry rifle and has two upper tang screws. The receiver has the early flat loading gate secured by two screws. The serial number is stamped on the left side of the lower tang beneath the stock, in the upper stock inlet, and on the inside of the buttplate below the lower screw. All of the visible serial numbers match. A staple mounted saddle ring is located on the left side of the receiver. The carbine has a 20-inch barrel and full-length magazine. The barrel has the early style upper barrel band with integral front sight blade. The first style, two leaf, carbine rear sight has a round 300 yard aperture and 500 yard center notch. The top of the barrel is roll-stamped with the first style legend: "HENRY'S-PATENT OCT. 16. 1860/KING'S-PATENT-MARCH 29. 1866" in two lines ahead of the rear sight. The hammer lacks a half-cock feature and has border-less, hand-cut, knurling on the spur. The brass, Henry style, buttplate has a sharp heel and hinged butt-trap door. The butt-trap contains a three-piece, jointed, steel cleaning rod with numbered sections and fine knurling on the flared handle. The stock and forearm are highly figured, fancy grade, walnut with a piano finish. The barrel, magazine and barrel bands have a blue finish, the loading gate and bolt are nitre blue and the hammer, trigger and lever are color casehardened. In "WINCHESTER BOOK" author Howard Madis estimated that the total number of First Model 1866 rifles and carbines manufactured at approximately 3,500 guns equally divided between rifles and carbines. He further estimated that the survival rate for these early Winchesters was about 25% and that "less than 875" First Model 1866 rifles and carbines were available to collectors. Madis also noted that deluxe stocks are rare on Model 1866 rifles. Deluxe features of any find are seldom found on Winchester carbines.

Exceptionally fine. The blue finish on the barrel and magazine has dulled slightly from age but remains 40% intact. The barrel legend is faint but fully legible. 50% of the nitre blue finish is present on the loading gate and traces of blue remain on protected areas of the bolt. The barrel bands have a mottled gray-brown patina. The hammer and trigger retain 60% of the muted original case colors. The lever has about 50% of the case colors and has aged to a mottled plum patina. The distinctive brass receiver and buttplate are in very fine overall condition with a good-looking patina. The receiver side plate joints are excellent and wear is limited to a few scattered scratches and handling marks. The buttplate is in very fine overall condition with a few minor handling marks. The fancy grain, burl walnut, stock and forearm are both in very fine condition with minor scattered handling marks. 90% of the original piano finish remains intact. This is a very fine example of an extremely rare Winchester First Model 1866 Flat Side carbine with, seldom encountered, fancy grade walnut stock and forearm.