In his accompanying letter of authentication, noted Colt historian and author John Kopec stated the revolver was previously listed in his survey and falls between to Artillery Models nos. 5013 and 5027 in the database. The revolver was manufactured in 1874, was sub-inspected by O.W. Ainsworth, and falls within Lot 5 (nos. 4500-5504) serial number range. Lot Five was one of the prime groupings of SAA revolvers issued to the 7th Cavalry from Ft. Abraham Lincoln on July 2, 1874, just before the 7th's departure to the Black Hills and Custer's infamous defeat at Little Bighorn. Kopec explained: "There of course is no positive way to determine if the subject revolver had actually been a 7th Cavalry issue. The physical evidence of the letters 'U.S.' being removed together with the letters "U.S.A." of the barrel address also being purposefully obliterated do speak of a recognized practice of that day which was frequently performed to those arms captured by the hostile Indians. This revolver's serial number #5020 is mentioned in our book 'A Continuing Study,' as being 'Presumptive, Obliterated 'U.S.', Indian use, rough condition' example. Several other examples from within this serial range including; #5056, #5099 and #6066 have been reported as having their 'U.S.' markings similarly removed." Kopec also noted the following: modified ejector rod housing, vise marks on barrel suggesting barrel had been removed or adjusted in the past, possible replacement hammer, non-Colt replacement trigger, re-blued, and replacement base pin. See "Cavalry & Artillery Revolvers...a Continuing Study, page 280 where is revolver is cited by serial number among a grouping of "Historically Associated Seventh Cavalry Revolvers." Matching serial numbers on frame, trigger guard, back strap, cylinder, and barrel.