Ccrider
Gold $$ Contributor
Ok. Now I get it. Never would have thought that a die .003 smaller at the base would only render 0005-6. ThanksNo, after spring back of the brass, a die that is .003 smaller than the fired brass will only yield about .0015 smaller at the shoulder and .0005-.0006 smaller at the .200 line after sizing. The brass near the base is thicker and harder than the brass at the shoulder, so it springs back a lot more and resists sizing down, hence the difference top vs bottom yet with the same .003 smaller die at both places.