Cleaning up an oily stock
There will always be a big debate on this issue, but I will chime in.
First, be sure the stock is separated from the receiver and barrel -- this may seem obvious, but some forget.
Second, I have watched videos where "authorities" butchered guns with oven cleaner in a tub of hot water and a wire brush. OWCH, that's Bubba the Butcher.
Third, I try to stay away from hot water, as it can warp the wood. Same with putting a stock in the sun, even in a plastic bag; or putting a stock in an oven -- these can result in a warped stock. (You might get away with it, but sun/heat warps stocks, especially when heated unevenly).
Fourth, diagnose the oil issue -- is it just crummy old linseed oil, or is it a cosmoline soaked stock? If it's just old linseed oil, rubbing alcohol and fine steel wool is probably enough to get the surface junk off. Varnish remover can be used if it's varnish. Denatured alcohol if it's shellac. Then you can soak overnight in turpentine or mineral spirits and then wrap in paper towels or rags or embed in saw dust, changing the "diapers" regularly to keep absorbing. (I've even seen people put it in cat litter).
Fifth, if it's cosmoline, use the turpentine or mineral spirits and fine steel wool then the "diaper" treatment.
Once the junk oil is gone, treat with BLO until it absorbs no more, rub hard with an old towel to polymerize the surface with hand-rubbed heat, then (and the purists will cringe) finish with tung oil. (Why? because BLO will turn brown over the next 10-20 years, and after 50 years will be chocolate brown; tung oil keeps the BLO from oxidizing, is a better fungicide, and repels water better.)
Just my opinion -- others may not concur -- but it has worked for me.
How the Stocks were originally finished
It might be helpful to know what CMP says about finish & red stain:
"The red is not a stain effect and not the color of walnut. It is the various oils oxidizing. It takes years for it to become the predominant color in the wood. Much conjecture about which component of the oil soup causes the most red could be voiced. One very quick gun oil to make a red shift is MILITEC Militec-1 Weapons Grade Synthetic Based Metal Conditioner, NSN 9150-01-415-9112. Left out in the light and opened repeatedly so that air got in, it has been seen to change from clear yellow to dark red in 6 months. The almost black color along the metalwood lines of firearms would indicate the gun oil has a large part to do with the red shift. Gun oil doesn't immediately hurt wood in small amounts on the surface of a good finish. Over time, gun oil dissolves the resins in wood and makes it mushy. For example, the compression effect of Garand receivers/trigger guards crushing the wood is in part caused by oil damage to the wood."
Any serious collector should see the whole article -- very informative.
http://thecmp.org/training-tech/armo...aning-article/
Unless someone has bleached the walnut, it seldom needs anything but BLO or Tung Oil. If it's another wood, a number of people recommend a combination of Gale Lock Dark Walnut Chestnut Ridge Military Stain (which is alcohol based and can be thinned with water or alcohol if it's too intense). See the CMP article for details on getting the right colour.