Looks like your stock absorbed a lot of finish in the dark figured spots and got a little rough, I had walnut do that and sanded it back to smooth with 400 grit paper and then green Scotch Bright pad before the next coat.
Go to 33.40 on this video to see how Kibler does it.
If you apply your finish with a piece of green or red scotch bright pad and scrub it in it will give you a beautiful satin finish and further fill the pores.
This is coat 5 with Tru Oil on walnut with a scotch bright pad, this way it doesn't have that phony high gloss finish that in my opinion looks out of place on an B/P gun. I did seal this stock with a stock sealer before I applied any Tru-oil.
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