Refinishing a Fox Sterlingworth buttstock that has black stained wood around the receiver. Probably accumulated oil from 1922. What is effective for removing it?

Expert advice is on the way, me I'm getting the popcorn. Seriously whiting is often used to remove oil staining from the head of a shotgun stocks like yours.

+1

Mix it in acetone to a paste if you really want to get it out. Wrap it in plastic and let it sit overnight. Repeat until satisfied. Heat speeds it up.

I think whiting is just diatomaceous earth. Sold in the bug killer section of Home Depot in bags. Not harmful to humans as long as you dont get it in your eyes.
Sitka is correct in how to use it and for heat I suggest on your vehicle's dash in the sun, in the bag of course.

I have had luck with acetone. I was never very successful with the whiting/acetone mix. First I use hair dryer or heat gun and it will bring oils to the surface, then wash with acetone. Repeating several times over several days. When I tested an old non-useable stock, I found it only got about 1/8" deep. If you apply a finish fairly quick (within a day or so) it will adhere before any new oil migrates out . I never could get all the stain out.Removing action from the stock gets a lot off the oil out of the in letting. Mostly I used this on old military firearms

If it is diatomaceous earth,
DO NOT BREATH IT!!!

Use a mask

Yep forgot about that.
It's the same thing as floor dry and kitty litter but ground to a powder.

Easy off oven cleaner works well believe it or not.

Yeah, but it wrecks the wood's cellulose in the process. One of the worst protocols to come down the pike years ago.

Absolutely correct!

When I worked at UAL I took oil soaked stocks to work to submerge in MEK all day. All oil was gone. Finished super good after. Wiping and whiting goes so far. So does heat. You are still at the surface. To bring gun oil up 1/2" is insane. MEK did it. I do not think you can get any. Nasty stuff. Submerge in acetone might work. Does no good to wipe the surface.

I've bought MEK at Home Depot.

It's often available at paint stores.

MEK is a powerful solvent, but somewhat hazardous to use in large quantities. Just do it outside and stay upwind. Minimize skin exposure with solvent proof gloves. No open flames.
Whiting is calcium carbonate powder AKA chalk dust. Talcum powder works as well just keep it away from your ovaries. Acetone is relatively safe for human tissue. Your body actually makes a small amount as a metabolic by-product. It is the principal ingredient of fingernail polish remover. The main effect is to defat the skin surface, but the skin will recover. MEK/whiting slurry is a good oil remover, but it is slow. Acetone/whiting slurry is also pretty good but not quite as powerful as the former.

A procedure known as "Wonko's brew" removes oil and old finishes is as follows:

Get a disposable aluminum roaster pan at the supermarket that is large enough for the
stock. Stop by your Home Depot or whatever and get a gallon of acetone and a
gallon of ethyl alcohol. If the stock has a plastic finish you might want a can of
some paste stripper too. Use that first if the outside finish requires it. If
the stock has a varnish or oil finish the acetone will lift that with no
problem. Then toss the stock in the roaster and pour in the acetone (it will
also neutralize the paste stripper). Cover the wood until it floats. Then pull
off a good length of aluminum foil and make a cover for the "tank", sealing it
as well as possible. Be aware that acetone is highly flammable and smoking the
cigar over the top of it is not recommended. Let the things soak for several
days, turning the wood over a couple times a day. When you feel like you're
tired of that, and the acetone looks like it has quit changing color, pour the
acetone back in the can, rinse the roaster out with alcohol, and then soak the
stock in the alcohol just like you did in the acetone. When you yank the baby
out of the alcohol bath it will be CLEAN! And you can seal it and refinish it
anyway you want after you let it dry a couple days.

RAN

Ha!

I've employed "Wonko the Sane's" brew and yes it indeed works, but it is slow.

After many applications of acetone and chalk the majority of wood was cleaned up satisfactorily. Light sanding 320 w/d improved wood surface. Stained with Arts formula Herter’s Red and wiskered. Masked checkering and applied Pro-Custom oil, wet sanded 400 for 5 coats. Cleaned checkering with DemBart single line tool and applied DemBart checkering oil sealer tot checkering. Installed new sear spring and we are good to go. Thanks for all the advice!

Let’s see some pictures

I cleaned up an oily Garand stock by putting it in my wife's automatic dishwasher with some dish washing soap. It cleaned it up real nice. It left the dishwasher a mess. After that I used Formula 409 and real hot bath water in the bath tub. (wear thick rubber gloves) I let them dry for a full day and then refinished it with stain and Formby's tung oil varnish. The black plastic bag in the sun works OK. I wrapped the stocks with paper towels to soak up any oil.

kwg

Try this: https://www.youtube.com/watch?v=Eb7WQTbXUlU

I've low boiled/simmered oil soaked milsurps in a strong mix of washing soda and plain water. Water turns close to black. No damage to stocks what so ever.