For de-greasing of old cosmoline I use mineral spirits mixed with Ford ATF, one quart to four gallons of spirits in an old bluing tank for a good long soak. On wood, to strip before re-finishing use oven cleaner. Depending how oil soaked the stock is, this may need to be done more than once. On walnut stocks I refinish with two coats of hand rubbed Tung oil, then seal with thinned linseed oil, also hand rubbed for three coats. Birch stocks get a thinned maghoney stain. Buff out with 0000 steel wool for military stocks, leave shiney for sporting arms.Oven cleaner will also remove bluing, beats all that polishing off the old finish prior to a re-blue. On light rust, use bronze wool and PB Rust Blaster, it takes it right off without hurting the original finish.