i can tell ya bout refinishing a sks!!!
i removed that "cake varnish"
and nearly all the red/orange stain crap.
steelwooled from hell!!!!!!!!! until smooth

applied tung-oil, rubbed it in....
prolly bout 10-12 coats.
and what a finish!!!!!!!
took several days of play'n but, here's the results.......

much better than the norinco finish...
before you could not see any grain...
the tung oil will bring it out.
i have never done a pw stock, cus i like laminates on my h&r's
i'll try one soon to see what it can do!!!!!