A Winchester rifle belonging to Mike Shonsey, who played a key role in the Johnson County War of 1889-1893, will be offered at Heritage Auctions.
It's expected to make in excess of $25,000 when it crosses the block on October 25.
The Johnson County War was fought between various cattle companies in the region of Johnson, Wyoming for control of grazing land.
Smaller ranchers and sharecroppers banded together against the might of the large cattle companies, who allied under the banner of the Wyoming Stock Grower's Association (WSGA).
Shonsey was appointed to end the rustling against WSGA members, a task he took on with gusto.
Following sporadic violence, the conflict developed into a full blown war - with the WSGA hiring gunmen to attack the smaller ranchers.
The war only ended with the intervention of the US army in 1893. Shonsey was responsible for one of the last killings in the episode, shooting his former opponent Dud Champion after he wandered on to his ranch.
Shonsey was later exonerated. It's unknown whether this is the gun that killed Champion.
Heritage comments: "Mike Shonsey owned and was photographed with this model '86, and either he or his employer bought it in Douglas, Wyoming, county seat of Converse County.
"This gun played a role, perhaps a deadly role, in the closing episodes of the Johnson County War.
"…it was claimed that Shonsey ambushed Champion. If so, because marksmanship with a revolver is so uncertain except at close range, it would have been prudent on Shonsey's part to have used his Winchester, this Winchester."
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