During the late 1950’s an early 1960’s, the Army Advanced Marksmanship Unit, (now known as the Army Marksmanship or AMU), at Fort Benning, Georgia used converted Colt 1911 pistols in 38 Special for National Match competitions. There was a concern however with the proper feeding of the rimmed 38 Special through the gun, as the problem was the difference in the position of rounds in the magazine between the first and last rounds. One of the AMU gunsmiths, Herman Gano came up with the ideal of the .38 AMU cartridge. The .38 AMU is basically a .38 Special with a semi-rimmed head, much like the .38 Super. Standard 38 Special cases were used with the head turned down and the addition of an extractor groove, combined with correct gun, virtually eliminating the feeding problems. The Army contracted with Federal, Remington and Winchester-Western to produce the 38 AMU cartridges. (Erlmeier, Brandt Ref. 352)