A model 1886 Winchester rifle presented to Captain Lawton for capturing the Apache chief Geronimo has set a new record for a gun at auction.
The lot realised $1.2m at Rock Island Auctions earlier this month, soaring past a valuation of $750,000 by 60%.
Pairs of pistols have sold for higher sums in the past, with a set presented to George Washington achieving $1.9m in 2002, but this is the most ever paid for a single firearm.
Auction house CEO Patrick Hogan said: "For decades firearms have provided an alternative form of investment and this is clear proof of that."
Lawson was presented with the rifle by a friend who worked for Winchester.
The lot also included a pocket watch inscribed: "Presented to/CAPT. H.W. LAWTON/4th Cavalry/BY THE/Cattlemen of Central New Mexico/as a token of their appreciation of his/gallant service in the capture of the/Apache Indian Chief/-GERONIMO-/and his band/Albuquerque, New Mexico/Sept. 27th 1886".
It bears the serial number 1, making it even more appealing to collectors.
Kevin Hogan, president of the auction house, comments: "Being serial number one and possessing such outstanding condition would alone be enough to draw six figures at auction.
"When you add one of the most famous names in the history of the Old West you have a huge crossover appeal and set the stage for something special to happen."
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