I'd also love to learn about the traditional walnut gun stock oil finishing methods. I understand it takes a day short of forever to accomplish it thoroughly though.
OK, Phil, it's late... but seeing that it's you...
There's traditional and there's traditional. If you keep pestering Chuck Burrows (or search "Wild Rose" on about any knife forum or on American Long Rifles) you will find a number of serious discussions on materials and application of "old traditional" gunstock finishes.
For decades now, most custom rifle builders, at least in this country, have been using urethane based tung oil (not "poly" in front of the urethane). Used to be the hot ticket was Flecto Varithane but it's not made any more (some makers have secret stocks of it still). The urethane modified tung oil a person can get is Pro-Custom Oil
http://http://www.brownells.com/.aspx/pid=5531/Product/PRO_CUSTOM_OIL_GUNSTOCK_FINISH. There are others selling it but it's all about the same cost. The story about it is at the bottom of this page.
http://www.gunstocks.com/digst.html.
I've got a friend who is one of the really good custom rifle builders alive in this country today... Joe Bautz, Lander, Wyo.
This is how Joe uses Pro-Custom Oil. Open the can and add 1T. of mineral spirits. That's like 1:11 or so. It thins the oil a little bit and causes it to dry a little bit slower.
Sand the wood and whisker it... two go-arounds with the same grit, then step up until reaching 320 ("real" 320, not "P", which is coarser... probably 400 in "P"). Whisker and sand at 320 until there aren't any more whiskers.
Take out a little bit of the oil and cut it 50/50 with mineral spirits. That will make the oil dry very slowly and penetrate very deeply. Flood the surface with the 50/50 oil keeping all wet by rubbing it around. You are looking to get all the more open pores to take as much thinned oil as they can... filling and sealing the pores. Add more as you need to, it takes a while for the oil to work into the pores. After the while has passed, wipe off excess oil... very lightly and always across the grain. Joe uses burlap or good, non-fuzzy cotton, but has been seen doing this with decent quality paper towel. You are looking to get the oil off the surface only. If you rub hard, and/or with the grain, some of the oil will come out of the pores and you wil rue the day 'cause you will spend a lot of time in the following steps, refilling them. On the other side, if you leave much oil on the surface, you'll spend a lot of time sanding back down to the wood (or end up with a cloudy finish). It takes a day or two for this coat of the oil to dry. Every coat has to be dry before the next goes on and, no, you don't want to know what happens if it's not.
Staying at 320, the 1:11 oil is sanded-in, dried, resanded in, dried, until the pores are filled... until ALL the pores are filled. It's tough enough to do this at 320, finding pores still needing filled at 600 grit causes a lot of extra work. Every step past this one is sanding the oil in with progressively higher grits. The sanding-in makes fines that go into the pores with the oil and fills them faster. Each coat is sanded to a slurry, let set a few minutes, then wiped carefully across the grain. Depending on temperature and humidity, there is a 8-12 hour wait for drying and a lot of times, it's just as easy to come back the next day... it will for sure be dry then. If you end up trying this, you will get a feel for dry or not by touching the wood.
As the grits are progressed though, the clarity of the finish changes. A person can (persons do...) sand-in up into the 2000's and then start finishing the finish with different grades of pumice stone on felt pads.
Many furniture makers would tell you never to go past 320 grit ("real") and finish the finish from that point or from the next grit lower a lot of times. There is a validity in that but it comes out of a world of finishes fairly different from urethane modified tung oil... finishes that build faster by quite a bit... and "old traditional" stock finishes build quicker.
In the end, the sanding in of the next coat HAS to take the remaining dried finish of the previous coat down to the wood surface. That's the secret of this type of finish... don't leave any extra on the wood to dry and make it really hard to sand through on the next coat.
http://www.acgg.org/about/ Goto ACGG Firearms Projects down the left side and fish around for the pictures..
Mike
Almost forgot... some people use steel wool. Steel wool wires hook into the tops of the filled pores and cut the finish and fines back out of them. Sandpaper doesn't do that. Use what you like, right?
Edit: I was just looking at some of the pictures on the ACGG site again, and thinking about all that surface area... kind of makes me happy about only using this finish system on itty bitty (by comparison) knife handles... =]