Actually,I did it once about 40 yeas ago.I was using some Bonna 2400 wood cross country skis back then,or trying to.Never did really become a sier...but living in Colorado,seemed like something to try.
Wood ski bottoms see a lot of water.And,the pine tar is a base for the ski wax.
I had a 35 Whelen on an 03A3 with the classical"at the time" basic cut down milstock.
After a little sanding and shaping was done,I pine tarred it.
You spread it on,then use a heat gun or propane torch to gently warm the wood till you see bubbles come out of the wood.As the wood cools,the tar will be drawn in where the air/steam was driven out.You want it on there like a coat of pancake syrup.Wet.
Rub it down good.You can oil over it.
It looked like a typical dark walnut military finish.
So,grab a chunk scrap walnut or other hardwood,give issome rounded shape,so its not a flat board,and try it.See what you think.
Its a utility finish,dark,flat.It worked for me till some guy offered me too much money for it.