Strip wood and all components. Purchase a can of lacquer thinner, rubber gloves and roll of paper towel. Take outside(need a well ventilated area), wet the towel with thinner and stroke a small area until paint is removed...won't take more than an hour to strip the entire rifle. Clean with additional applications of thinner. When satisfied oil the rifle. This is much more effective than paint strippers as they sometime react with the metal finish.
If this doesnot work then the rifle has been Suncorited and the only way to remove it is to bead blast. The rifle would have to be reparkerized or blued. Suncorite is a correct factory finish.
Good luck with the project.
Ron