Page 40 "Although there are exceptions, butts typically range in depth from 5 1/16 inches to 5 5/8inches........In general, a 14 1/2 - inch stock should have a 5 1/4 inch butt, and one that's 15 inches long should go 5 1/2 inches deep."

Page 44 "The standard width is about 1 5/8 inches for a 12 bore but may be a bit smaller according to the gauge of the gun"