I bought a product called "Purple Power" from an auto parts store. It is probably the same thing as Simple Green. I take the guns apart, put them in the bathtub, fill a spray bottle with purple power and spray down everything. I leave it sit for like a half hour. Then spray it again and scrub with a toothbrush. I then hose it off and let it dry. If it didn't get it all, I do it again. At that point you usually have to give the stock a few good coats of linseed oil.