David, I'll try to answer some of your questions with some qualifiers: If the wood is one of the American walnut varities which it looks like it, I have found this porous wood to generally be more brittle than smaller pored wood. This would make stocking the gun more difficult. Open pored wood is, as has been stated above, a lot harder to fill than small pored wood. Oh, and it checkers like dog doo doo.
IMHO, you're much better off buying a nice dense small pored blank to make a stock from and drill lightening hole in the butt if needed.
