any .470-.473 bolt face small primer usage

[QuietTexan]

your choice on small magnum or standard primers

I don't use CCI-400s in really anything, those are for lower pressure cases. The 450s are marked magnums but that's my go-to across the board. Same deal with Rem 6.5s, no reason to not just use the 7.5s.

The difference is primarily cup thickness, the "non-magnums" are thin enough that they can piece on high pressure rounds. BR-4s should be same cup as the 450s.