Car wax can be used to protect both the finish on your car and your gun. The finish on the gun is already water proof, but large areas of the wood are not protected by any finish. This should be remedied. The inside of the forend, the front end of the stock where it contacts the receiver and the butt end covered by the recoil pad are usually raw wood. A coat of varnish on these areas will protect the wood much more than a layer of wax on the finish.
Shooterlll, What about boiled linseed oil? It is my understanding that is what was used for the classic hand rubbed oil finished stocks. I have used it forever and over time with lots of elbow grease it gives a beautiful finish. Smells good too. gyrine
Unless you have a very high end, oil finish, Beretta....its not an oil finish. Its a matt finish poly urethene. Wiping a wood oil on it will do NOTHING.
If you want it to shine a bit more, then furniture polish (Pledge) and time will do it. You can also go the route Pat suggests....try good car wax...to me, that would be Mothers Carnuba. Do NOT use anything with abrasives and many synthetic waxes do have some degree of polishing components.
The real guts of Pat's recommendations has to do with sealing the generally not well sealed parts of the stock....the inside parts. Varnish or wax will help seal these areas and the interior of the wood from water penetration (assuming you shoot targets or game in the rain).