If it's a 70# bow, and you want the most out of it, why not just crank it all the way - provided your accuracy and form do not suffer. If you've been cranking it up little by little, to crank it up another 1/16 of an inch would probably only give you another 2-3 #'s.

My brother had heard that for every complete turn of a limb bolt, you gain/lose approx 4 #'s. Can't verify that though....

Jim.