Expert's Corner — rubbing

The most popular homeowner gunstock finish is probably Tru-Oil. You can get it at almost every store that sells guns. Tru-Oil is polymerized linseed oil. It is linseed oil that has been cooked at high temperatures in an oxygen-free environment (inert gases) until it just begins to gel, then rapidly cooled. The cooking causes the carbon atoms to begin crosslinking. So when the finish is later exposed to oxygen in the air during the finishing process, the finish cures very rapidly. After the cooking the oil is very thick so the manufacturer adds mineral spirits to make the finish easier...