I'm posting this here because I figure it will get seen and answered sooner here than in the reloading forum. I am about to get a Coharie MP5 / 10 and I reload for it and my Glock 20. I load 180gr bullets to 1150 in my Glock. The FBI load is 1130 in a 6" barrel so that makes them a little warm. My concern is if I can still get multiple reloads with my brass if I continue to load and shoot them in either gun or will I start having higher incidences of case splits? I only get case splits in the Glock ever few hundred rounds as is.

My Coharie BCG gouged the remaining case at the top of the mag as it chambered the round above it, this damage led to the case splitting on the next reload. I smoothed the sharp corners of the carrier which helped but ultimately I replaced the BCG with a German one in order to achieve reliable FA function. The German carrier doesn't damage the brass.

I have a 165 grain load that runs over 1500 FPS in the Coharie and case life seems decent with some going on 3 or 4 loadings at this point. The real challenge is finding your brass as the HK MP5's sling them into the next time zone, I added a railed hand guard and a brass catcher!