Only if your reamer is too short, and your sizing die doesn't size to the shoulder.As I understand it ....... You ream thick necks and forming donuts .
You turn the outside to provide uniform thickness and better chamber centering of the neck .
Was it worth the extra time and effort? And what do you mean, "Square the base in the trimmer"?Ian, my solution, for match 30/06, to that was to FL resize in an LE Wilson old style die with an arbor press. Then remove the case and square the base in the trimmer. Then I fireform and measure for neck wall thickness. After turning, fire in the same chamber and it will be as close as possible on centerline of chamber, but not necessarily the bore. Every case only goes into one rifle. Ric
Was it worth it? Don't know for sure, but won three CBA National Military Rifle championships over the years with the same 400 case lot of brass.Was it worth the extra time and effort? And what do you mean, "Square the base in the trimmer"?