While I agree FC is part of the problem, the 38 Super brass is WW RP FC ... . I have also had Norma brass have loose pockets after firing it as factory ammo. I'm trying to determine if QC on the brass is bad, or QC on the primer dimensions are bad.
Some is Good---More is Better----Too Much is Just Right
The primers I have vary by brand as much as .002 in diameter and primer pockets vary in diameter also, even when the cases are new.
They also vary in diameter from lot to lot. As far as the primers I happen to have at the moment the WLR's are the smallest at 0.210 and one lot of CCI 200's are the largest at 0.212. Federals are in the middle. There is a huge difference in seating pressure between those sizes.
A different make of primer may have a larger diameter and be worth trying. I have a few hundred Lapua .308 cases that I put back into rotation after trying Unis Ginex SRPs.
I too have found these Ginex SRP primers to be slightly larger in diameter than others.
