Ive been fooling around with a Redding FL Die and a RCBS Small Base Die set for my AR-15 in .223. I set both of these up to bump my shoulder .003" But here is where im confused. I cannot find where at on the case the Small Base Die resizes the case any smaller than my Redding FL Die. What portion of the case is the Small Base Die supposed to resize differntly or smaller than my standard Redding FL Die? From my measuremnets all of the dimensions are coming out the same.