First of all, i mill all of my own lumber, includeing some stock blanks, here's a walnut going on the mill, (can you see the anchorseal on the end of the log?)
I mill out, both lumber and stock blanks, it depends on what THAT log will give, as not all walnut will turn out good stock blanks,
For gunstocks out of walnut, you don't need to quartersaw. In fact flat sawing makes a much nicer stock, and anyway stock layout is MUCH more important than quarter vs flat. Just sawing out thick slabs does NOT make your best, strongest stocks. See how i milled this walnut so i can get good layout,
I can't stress enough how important the "layout" of the stock blank is!!!
Then use Anchorseal on the end grain and highly figured area's, or even melted wax, oil paint is the WRONG thing to use, and latex works, but it works poorly!
Once that is done, the blanks need to be stacked on stickers and covered to air dry,
After a couple years, you can move the blank inside a house for another 6 mo. or longer BEFORE you start butchering it!
DM