Sure it will! Gunzilla is enough for anything in my book. Thing is.....I wouldn't want to waste any of MY Gunzilla on that project. I think it's intended for better uses as far as I'm concerned. De greasing long term stored firearms can be tedious. I'm sure Gunzilla would make it a quick chore. My opinion? If I could sell you a gallon of Gunzilla, I would, but I think your Gunzilla would be best saved for after the de greasing project and used for it's better intended purposes. It depends on how heavily your pistol has been preserved. Personally, I'd strip it down with hot water and dishwashing liquid, or some of the other recommended practices (Google cosmoline removal) and then start with the Gunzilla from the ground up. Sort of like taking a clay bar to your car...break it down to the paint, start on a clean slate, then let Gunzilla be your sealer and wax. Either way, Gunzilla is something you should have to care for that prized pistol, your every day carry, your one week a year deer stalker, your competition gun, all of the firearms you love. I say use it wisely, and place your order today. Tomorrow will never be the same.