I'm sure some of you have watched it. There were a lot of comments theorizing what happened with the 6 ARC load and why the belting. I'm pretty sure to much of the wrong powder was mostly to blame. But a lot of people were wondering about case differences including me since I've gotten a little belting on my Laupa brass. So I hacked a few open.
Left to right Lapua grendel, Starline grendel and Hornady 6 ARC
Left to right Lapua grendel, Starline grendel and Hornady 6 ARC