RE: Mobil 1 for your Car..how bout for the Rifle
True - it will also, over time, gum up any mechanical device. I periodically get in rifles that are misfiring. First question is usually "did you ever use WD 40 on the bolt or trigger mechanism?" If so, a trip to the solvent tank (or a good soaking in a coffee can of gasoline, if out in the field) will usually take care of the problem.