Just want you to benefit from my error. Had an new Ruger Bearcat long ago that didn't get shot very much. Didn't have gun oil, so I used WD-40 to lubricate it and store it. Got it out a few days ago and the cylinder would not lock into place. Gunsmith said WD-40 solidifies after a while and had caused the cylinder lock to freeze. WD-40 works best on door hinges, not guns.