+1 for what Cosmoline said in his post.
And here's a quick summary of my own experience. First I like working wood. I'm one of those guys that slams on the brakes on a Saturday morning when I see an old dresser out by the curb. Truth is that the older the better. Nine time out of ten you will find that people through the years just slap on all kinds of paint and you never know what is underneath. Now to Guns and Mosins in particular. The problem here is that you have several arsenals and also many years, so its tough to tell where your particular rifle has been or what it has been through. So begin by removing all the old stuff.
On mine, the day I got it home I took it apart. Not fully, just separated the barrel, magazine and stock. When I looked underneath, the magazine area was black as the Ace of Spades, but up front, the top fore arm cover and bottom front of the stock were a reddish Walnut color. I know the Ruskies were turning Mosin's out using a Beech Laminate, and Beech wood is not this color naturally but I did like the color. I'm guessing that the stock was probably dipped in some stain solution originally, but then sat with a cover of cosmoline over the exterior for many years prior to coming to this country. This would have eaten away any color in the original stock exterior.
I began by stripping down the exterior of the stock using Acetone. I then neutralized the Acetone with just a Steamy damp rag. Next I started with a pretty coarse grade sandpaper until almost all dings were nearly removed. There was a good deal of oil that continued to clog the sanding block I was using, but it is the newest sanding stuff that you can bang and clear out the oil soaked wood dust. You have to keep at it until you reach a point where the sandpaper is not clogging any more indicating you are at wood only. At that point I went to a finer grade 120 I think, and some more elbow grease. Once smoothed, I then went even finer 180, then 220 until the stock was as slick as a baby's bottom. The color at this point started becoming a more yellowish dirty grey. Off to the local hardware store for some high end stain. There are two types now a days, very watery type, or a gel type. I started with a watery cherry stain on the HW guys recommendation. This was too red and made the stock turn out almost pink. However, the next layer of stain was the gel variety and it was a dark brown Walnut color. The final color exactly matched what was on the underside, and I am extremely pleased with the results. I looks better than the day it left the Ishy factory. I toyed with the idea of spraying on a glossy modern day acrylic finish but thought it might be too much. Instead, I have rubbed it out just using a rag and Pledge household polish. This produces a soft luster. The final step is to use a Hard Carnuba wax,(Mothers Gold at a Car part store) several coats, and lots of the Mister My Ugie "Wax on - Wax off" I'll have to post a picture of the finished product in the next day or two.
KKKKFL