The Ruger Standard Model .22 pistol antedates the BATFE definition of a firearms receiver, which was promulgated in the aftermath of the Gun Control Act of 1968. Ruger did not want to stamp serial numbers into the Standard Model .22 pistol grip frame because it was two stamped halves, welded together, and somewhat fragile. ATTU had no say in this in 1949, as long as the pistol had a serial number somewhere. Several handguns made after the Federal Firearms Act of 1938, which first required handgun serializing, had their serial numbers stamped on the underside of their barrels.