Accidental firing defect in early model Ruger 22 cal pistols?

Answer 1

Early model (pre 1973, if I recall) Ruger single action REVOLVERS could fire if the hammer was struck, or the weapon dropped onto the hammer, and the hammer was resting on a loaded chamber. Ruger implemented a voluntary recall, and installed a hammer block to prevent this from happening. The design was changed to a transfer bar system that will not fire when hammer is struck. FWIW, the old style single action revolvers from MOST makers would do that- best practice was to keep hammer resting on an empty chamber. Do not know of a problem with ADs from their PISTOLS, just the revolvers.