rewinder said:I have made 6mm-22/250 A.I. from 308 and 243 brass and Again down to 6x47 A.I. Take about eight hours for a hundred pieces of brass Half an hour for 6X47 a.i. from 6.5x47 Randy
Asa_Yam said:The "mushrooming" results from reshaping the shoulder angle,and pushing it back). It happens with most forming methods for 6XC as well. A fireforming with a good, stiff load usually takes care of the wrinkle.
The same thing will happen if you try and form a new 243 win or rem case in a 6 br die. But if it is a fired case it works pretty good. Solution, 243 lapua into a 6br small body die, no mushroom!