This is one question where the suppliers are happy to explain how they grade the wood. Dick Greensides at Pecatonica Rifle Works has been selling wood for over 30 years. When you order a stock, or go up to his shop to pick one out yourself, he tends to give you one grade better than what you ordered, or charge you one grade less than what you Think it should be, even after he explains his grading system!
I don't know that there is a written set of rules or guidelines on grading gunstock wood. Most of us recognize utility grade wood, whether maple, or walnut. Some of us recognize the highest grades, because of the breathtaking grain patterns, and fiddleback. In between, Most of us would have a problem. I can recognize the " Fade " where you have nice grain and fiddle back on one end of the stock, but not on the other. But, beyond that, I listen to the experts. Dick Greenside is one of the experts. He is set up at Friendship on Commercial Row for all the major Shoots, and you should certainly expect to find him there the second week in September. You can call him at his shop( Get contact info off his website, and you can find that on the " links " section here under Member Resources) and talk to him about what you are looking for, or what price range you want to spend.
Dixon's Gunbuilder's Fair is coming up in a couple of weeks, out in Pennsylvania, and there is always a truely competent, and knowledgeable wood expert there, selling stock blanks. Chuck Dixon is also a good man to talk to about grades of wood.If you look at the website for the fair, it will list the speakers, and there is almost always a presentation by the expert on woods. I sat in on it back in 2003, and learned not only how he grades, wood, but how to read the trees for some( not all-- Birdseye maple is very rare, and to date, there is no way to recognize such a tree from looking at the bark) grain structures by simply looking at the bark on the tree! That was fascinating. There are suppliers on both coasts, and in Missouri, so a phone call to the closest one should not break the piggy bank. In my past, I bought wood from both Bishop's Stocks, and Reinhardt Fajen, both in Warsaw, Missouri, out of catalogues, and after talking to them on the phone. Both firms are now closed. Boyd's has some of the operation that was Fajen's, I am told.
All of these businesses are considered " small " by today's corporate standards. They don't have separate order departments, and complaint departments like GM. If you call, chances are that you will be talking to the owner! Don't miss that chance. You will learn a lot, and make a good friend.