By my reading Tung Oil is toxic and some people are allergic to it. People who look I think will find recipes for oil finishes here that are superior to what you can buy. I have a formula for a a rosin/gum benzoin brown varnish but have not made any yet. I have made various batches of heat modified hardware store "boiled" LS oil that I have used a lot. Nor is it that slow to dry is if its properly made considering the store bought boiled oil as a raw material. But I have found that some batches seem to need to be reheated if in storage a long time. Mad Monk might he a help here. I won't put any of the synthetic finishes on a gunstock most will fail in a few years or maybe 20 and this includes Permalyn from reports I have read.
The Rosin has to be mixed with REAL high grade Turpentine to mix with the oil and gum benzoin with a good ethyl alcohol or moonshine. Denatured will work but we never really know how it was denatured. If making gunstock varnishes making more that a pint in a mistake in many cases unless it it decanted into smaller sealed bottles. Pint of oil, my friend recommended cold pressed food grade oil and the dryers added during the varnish making. a 1/2 pint or more of Turpentine (which will also add resin) enough to dissolve the 2 oz of powdered rosin, enough alcohol to mostly dissolve 2 ounces of gum benzoin. It will have a lot of dirt and junk in it but powder it up with a motar and pestle and use it. For traditional varnish a teaspoon of lead carbonate can be added as drier. I will likely use this and some Japan Drier as well. The original varnishes had dirt in them from the same source. I would give other details but I have not made and tested any yet.
I think somewhere in the archives I have described making boiled oil for fill but with no or little added resin it makes a great filler or fits coat with good turpentine added but it not as good as a top coat since it has little resin. I have made varnish by added Grumbachers Oil Painters Medium III 50-50 with oil I have heat modified "boiled LS Oil" (acid killed, thickened and drier added by heating in a deep fat fryer). Its works pretty well this way. A heavier oil varnish will often give a satisfactory finish on hard maple with on soaking fill coat cut about with 20-25% Turpentine. Excess turp can result in to little of the oil finish IN the wood. The natural oil IN the wood is what enhances the figure in the wood. While it will be dry enough to use is a day with the excess wiped off in an hour or so it will not fully cure in the wood for a few days and full color will not appear for some time. The photo is 3 coats, a seal coat and 2 thin, spread with the hand finish coats. But it a couple of years old or more here. In the first couple of weeks after application its not this bright. And its best set in the sun to cure. Which greatly speeds curing time. And the really thick oil I use for fill will allow 2 coats a day but will not COMPLETELY dry in this time but will gum up enough to stay in the pores of the wood when rubbed off with OOOO steel wool or burlap. Varnish is often too hard for this since I put on really heavy coats on Walnut and it would be difficult to remove. Example, Birchwood Casey "Tru-Oil" is especially bad if not reduced with BLO.
The only store bought oil finish that I have had good reports on is Jim Chambers oil.
I would avoid any finish with petroleum solvents since they are a health hazard due to the toxic fumes. Plastic finishes, IMO have no place on firearms of any kind and especially on a longrifle. Having stripped the plastic off some modern guns and refinished I can tell you there IS a difference.
Finally if you have to put on 7 or 8 or 20 or more coats of finish you are REALLY using the wrong stuff. Most original rifles even factory mades in the late 19th c had one coat of finish. But it was a heavy bodied fat oil varnish and had little or no penetration. This is true on many ML arms as well. Like the Bridger Hawken in Helena.
This is a seal coat and 2 thin finish coats on plank sawn hard Maple.
