If our log is wide enough to get a gunstock out of the middle, it will have to be at least 30 inches, and probably larger, to cut a 12 inch board from each side of the heart wood, and back from the bark wood. You should cut the tree before the core rots out at all.
If you don't want to quartersaw it, you can bring your saw blade 1.5 inches off dead center each side and cut the center board, which can then have the heartwood ripped out.
You may be able to plain saw another good board each side on even a log as small as 36 inches, while still retaining good grain, and picking up figure that is not too different each side of the board.
See if you can find a local lumber yard or cabinet shop with a kiln to help dry your wood more than you could do air drying in years. Best of luck.
I don't have the link to the rifle I posted made from black walnut grown on my farm. It is really blackish, too, but turned out well. If you cannot find it, a Mauser 6.5x55mm takedown, I can send more photos.
