Steve:
I must confess that I really don't know a lot about the Blue Book.
I only know that the it seems like the guns I am most interested in are pretty consistently over valued by the Blue Book.
This may not be the case on guns that I am totally ignorant about. Which outside of 99's, 1911's, M1 Garands, M1 carbines, and Remington model 8's and 14's includes about every other gun on the planet.
Randy