This experimental Smith & Wesson "Project XR-357" is documented in "My Life Journey with Smith & Wesson" by Dwayne W. Charron, former Director of Research and Development (copies of related excerpt included). In this writing Dwayne says, "The next project to come along had been requested by the plant manager; it was called 'Project XR-357', which stood for 'Experimental Revolver .357 caliber.'... We were to explore new methods and materials that would produce parts to near finish configuration with a minimum of machining and to assemble or selective assemble rather than fit. We were not going to change the basic Smith & Wesson design, but rather how it might be fabricated... We wanted to make the barrel part of the frame. We chose powdered metal as our process... The cylinder was the only major part that we fabricated using regular production methods... The small parts, such as the hammer, trigger and sear were made from powdered metal... We completed parts for 30 revolvers and conducted many tests for accuracy, wear, function, ease of assembly, as well as interchangeability of its parts. There was never any intent to produce this revolver. As explained earlier, it was strictly a research project and was completed in mid-1979." The serial number "19" is stamped on the inside of the frame, and is the only visible marking.