In late 1969, Dale W. Hoffman was Superintendent of Small Arms, Machinery, and Plating at the Rock Island Arsenal. Hoffman had noticed that a shortage of the Colt "Model M" or Model 1903 Pocket Hammerless pistols had arisen, the pistols that had been issued as general officers pistols since World War II. At his own expense, Hoffman made and submitted a prototype, and unsolicited proposal, of what would eventually become the U.S. Model M15 General Officer pistol. The proposal made its way all the way to Washington before the project was approved. Initially, three prototypes were built using re-purposed Model 1911/1911A1 and Government Model parts, one of which received a blue finish, and the other two a chrome finish. All three of those prototypes were believed to have been used up in government testing against candidates from Colt, Smith & Wesson, and Walther. In April of 1972, a request was made for six more prototypes, all of which are believed to have received the blue finish and fairly standard markings, after the chrome finish was rejected. This specific pistol appears to be one of those six prototypes and appears to be pictured on p. 164 of "The Colt U.S. General Officer's Pistol" by Horace Greeley, where it, or a nearly identical prototype is pictured on a peg board along with the other potential candidates at Rock Island Arsenal. This pistol or one similar is again pictured on p. 165 with its competitors, and again on p. 166 by itself. The pistol is not identified by serial number, but shares all the visible markings and features that this pistol has. The left side of the slide is marked "General Officers Pistol/Model 1970". The right side of the frame shows faint U.S. property and Model 1911A1 markings, as well as a restamped serial number. It is fitted with a flat topped blade front sight, just like the pictured example, and high notch rear sight. The grips are checkered walnut with an inset R.I.A. badge in the right panel, and the left panel lacking the polished nameplate which was added in standard production. Unlike the standard production pistols which received a matte black finish on the top of the slide, this example has a complete, high polish blue finish. Includes a hardwood presentation style case with brass plaque on the lid marked "R.I.A." and brass plaque inside the lid marked "General Officers Pistol/Rock Island Arsenal Prototype/Model 1970". The interior of the case is fitted for the pistol and lined in dark green velvet. Also included is a copy of the above referenced book by Greeley.