The Ainsworth or OWA Colt refers to the earliest issued Single Action Army guns, which were inspected by Orville W. Ainsworth. Ainsworth was the ordnance sub-inspector at the Colt factory for the first 13 months (October 1873 to November 1874) of the Single Action Army's production. It was Ainsworth who inspected the Colts used by
Col. G. A. Custer's
7th Cavalry at the
Battle of the Little Bighorn. The number range of possible Little Bighorn Colts is 4500–7527. (Wikipedia)