Manufactured in 1869 as a third model with the serial number stamped in block numerals behind the trigger. The barrel has dovetail blade and folding ladder sights and is marked with the two-line Winchester address/King's improvement patent dates. Sling swivels are mounted on the underside of the forend cap and buttstock. The buttplate has a compartment (cleaning rod not included). The Model 1866 was the first firearm built under the Winchester name and secured Winchester's place in the annals of the West.

Fair. The barrel and magazine retain a mixture of smooth artificial brown and gray patinas. Traces of original nitre blue remains on the loading gate. The brass has mostly a mellow patina. The refinished wood is good with a spliced in repair visible near the upper tang, a couple hairline cracks and some minor-moderate dings. Mechanically fine.