Perhaps in an effort to not do the wrong thing to a stock you intend to keep, you could find a lesser quality stock, cracked or damaged and experiment on that first.
I may be wrong but Tom's products are more aimed at US military walnut stocked rifles such as 03/03a3/Garands..
I never post here anymore, but for the OP I have to. Take another look at the link Hambone posted, and read "Linseed Oil Varnish" one more time. The Germans used this on the wood to keep it from drying out, and if you don't treat your wood with something, it will dry out and become useless.
I'm in agreement with most collectors when they say don't use BLO or Tung Oil, because its something the Germans never used, but Raw Linseed Oil is a different story, and is not harmful to your stock.
Everyone who reads this post needs to understand one thing, you may currently own more than a few rifles, but you guys need to start thinking long term. We are caretakers of these rifles, regardless if they 98ks, M1 Garand's, or South American Mausers, and not treating the wood properly will do damage because the wood will shrink, or possibly dry rot.
I have seen more than a few 98ks over the years that were totally factory matched that were ruined by someone shooting them with dry stocks. Some will crack at the wrist behind the receiver, and in at least one case, the recoil crossbolt started setting back into the stock. When this happens, your rifle is all but useless.
I keep hearing how Linseed Oil will darken the stock, and my answer to that is so what? I bet it was slightly darker when Uncle Bob, or Grandpa brought it home, and do know why? Because the German that owned it actually took care of it. When German Soldiers did not have Linseed Oil, they would use anything they could to include; cooking oil, sun flower oil, and even motor oil. I know this to be fact because I've actually spoken to several German WWII Vets when I was visiting the In Laws in the Iron Mountains.
Fifty years from now, every 98k that I own will be in the hands of someone else, hopefully to another collector that will get lots of joy out of them as I do. The difference between my 98ks and others will be mine can be shot without damage to the stock because its completely dried out.
I'm positive the usual suspects will pile on after this post lamenting on how I've "ruined" my rifles from just a little bit of oil, but I'm not taking the bait, and will ignore these so called "experts".
If you believe what I've said is BS, I urge anyone with that dried out "all original" stock to head out to the range and put 50 rounds of Milsurp grade ammo down the pipe. Maybe nothing will happen, but if your stock cracks, remember, you were briefed.
The Germans original finish was "linseed oil varnish" with sometimes the combination of a stain until they started leaving the factory with nothing on them later in the war. Another product that purists were using is this http://www.howardproducts.com/prod-feed-n-wax.php
I read this on another forum
Has the cosmoline been sweated out of the stock before this fool's errand was undertaken?
Thanks for your skilled comments. I'm not sure if you knew this or not, but it is a sin to sand your stock. Yes, the cosmoline has been properly removed. I ended up putting 2 coats of Howards on it instead of Toms 1/3 Wax and it turned out great. Good luck.