I picked up a USGI walnut m14 stock. Mostly it is lightly used except for one digger near the wrist which I am gonna try to steam out. Also has some cosmoline on it. What is the best way to remove that? Just heat and wipe?
What was the proper way the stocks were finished? Linseed? I know Garand Gear has some that is the right stuff for Garand stocks. Did they do something different with the m14?

Yep, that!

Steaming will take the rudeness out of dents.  

It depends on what you want /need.   Boiled linseed oil or Tung oil is traditional and military correct.  They are easily touched up by adding more and letting it soak in then wipe off excess.

If you want a better seal for avoiding more rapid moisture movement into the wood, or might expect to have to shoot a match in a rain say in a NM rifle set up, then a polyurathane type finish will better seal the wood and be more durable.  The downside is to refinish right you might have to strip it.

Your gun your call.

Cosmoline removal,....i’d go with wiping with mineral spirits to get the bulk off.  Then switch to clean rags and alcohol.  If it is heavily saturated with cosmoline and oil in the wood I’d skip the polyurethane and stick to tung oil (or BLO).  Not being able to remove all the penetrated oil might get to be a problem with poly, not getting good adhesion or even lifting the finish later.

Steam out the dent and hit the thing with some tung oil.  If it has any cartouches or markings do not sand it.

Ya it has cartouches, outside of the one dent the stock seems very lightly used.

Leave it outside in the sun on a hot day, then start wiping.  Cosmoline may seep out of the wood for some time, so be ready to keep wiping.

Yes, original M14 stocks were finished with BLO. It was also provided to armories in rectangular cans for refinishing.

Older Garand stocks were finished with Tung oil before BLO replaced it.

In modern times you've probably seen lighter colored M14 stocks in the hands of honor guard or drill team members. These are usually birch stocks which have been sanded and refinished with polyurethane.

I used to use BLO on my CMP M1 Garand stocks.  All walnut.  Then I ran into a couple H&R stocks that looked sandblasted no matter how many coats of BLO I put on them.  Tung oil was recommended to me and I tried that and it shined them right up and seemed to smooth the surface out nicely.  Been using Tung oil every since.

In the Army we used some stuff called Linspeed oil.  Never paid attention to a difference between Linspeed and linseed because I didn't even know about linseed oil back then.  The Linspeed oil worked great, too.

CitriStripper to remove the cosmoline and old finish.  CitriStripper is a furniture finish remover, so it won't h hurt the wood.  It will probably take more than one application.  I often scrub it off with a soft brush and hot water in the shower.  If the wood is walnut, I may use some crystalline Oxalic acid wood bleach, which does a good job of lightening the the wood and high lighting the grain.  If I want it to get the look of old aged stocks, I apply one, or two, coat/s of Raw Linseed Oil(Flaxseed oil is the same thing, just food grade).  Followed by one, or two, coat/s of  Boiled Linseed Oil, or Pure Tung Oil.  
The Linseed Oils will age and turn the dark reddish brown that one sees on old military stocks.  RLO will turn color a bit quicker than BLO.  PTO does not change color.
If the stock is Birch, and has some figure, I may use a thinned stain with some red in it.  Usually applied after I have one coat of finish on the stock.

Citri Strip is some great stuff to have on-hand.

Tung oil has better water-resistance than linseed, and I've found I need to reapply a refresher coat far less often, not that linseed is garbage or anything.

I did mine with several coats of RLO. Turned out pretty nice IMO.

It's the other way around.  Wood stocks used to be finished with RLO until 1942 when the US Army changed over to tung oil.  Tung oil produced much less smoke when the weapon was fired for extended amounts of time.

RLO in my experience will oxidize to a chocolate brown.  

I accidentally hit a dry 1903A3 Smith Corona stock with RLO.  It was a beautiful red toned walnut,....a year later it was chocolate brown.  

I much prefer the red tones but it’s authentic with RLO too.

I haven't had that happen with mine....yet. Its been several years though. I wonder if it depends on the maker and application process?

f I use RLO I usually put it on fairly thin and rub it in  then let sit a week or more before the next coat. Only do 2 or 3 though so not really soaking it in. I have had good results with raw tung oil in the same way.