In 1987 Scott Meadows published U.S. Military Holsters and Pistol Cartridge Boxes. It is the canonical work on the subject matter with really no peer. It has been out of print for many years, hard to find on the used market and expensive when a copy could be found. His revised version, slightly re-titled, is now out. With nearly 30 years of additional research, U.S. Military Holsters and Related Accoutrements is again without peer. You won't find a more complete volume on the subject. 836 pages.