Well, I took my rig to the range. I elected to shoot the federal GMM first. I shot a 5 round group and it landed a group that was bigger than desired (see image 1). When I looked at the brass, I could see clear ejector marks (see image 2) again, this was factory FGMM.
I have found pressure signs on my hand loads in the past but have discontinued at the first sign. Noteably, I have gotten pressure signs at what I believe to be rather modest charge weights.
I contacted rainier via message, I hope to hear back soon. I’m a little disappointed that I’m having an issue, but I’m not going to be very quick to blame rainier. The good news is I will be able to test the quality of rainier’s customer service.