I don't know if this is any help, but it's a good check to make sure you have the right size bit before you mount stuff (I'm real picky about pilot holes and the various materials that I'm drilling). I always try to anticipate what I'm going to be working on well in advance so that when I drive by a Home Depot, or similar, I can run in and pick up a drill bit or two taht I might need. Let's face it, most of the holes we drill into wood, for wood screws, are going to be #2, #4, #6, #8, or #10. The pilot holes, be it for soft hardwood, or hard hardwood, are small, so the price of a fresh bit is usually just a buck or two. A small price to pay to have a smooth project. Believe me, I learned the hard way that the often times seemingly trivial aspects of fitting a piece to your work can be the show stopper. I've barbequed brisket over more than one piece of GOOD project wood.....
http://www.boltdepot.com/fastener-informat...-Hole-Size.aspx