RB Roosen,
If it needs total refinishing, try using Citri-strip on it, before you sand it. I have done many stocks using it, and the tung oil finish. Once the stripper has the stock cleaned off, you can wash it down with paint thinner, and let it dry. If it needs major sanding, do the heavy stuff, then when it just needs some fine work, use wet and dry sand paper, and dip it in a mixture of tung oil and paint thinner. That will allow the tung oil to penetrate real deep, and help with filling the grain. As you go to finer paper, keep adding more tung oil to the mix, until your satisfied with the smoothness of the finish, and then apply tung oil using your hand until it has the sheen you desire. You may need to lightly sand with 600 grit paper in between coats. I have done some stocks with as many as 40 coats of tung oil, but that was for a glass like finish. Good luck with your project, and have fun with it. Just remember, if you don't like the way it turns out, you can always strip it again. The tung oil, and Citri-strip is available at Home Depot, the wet and dry sand paper can be had at auto parts stores.
Don
