I shot a bunch of the PNTC DMR matches from the time Tom P. started them until probably several years ago. I've seen some matches starting to come back to PNTC so I'm going to be on the look out when they come up so I can hopefully attend.
My experiences have been similar to ClangClang, a well set up 5.56 rifle with a 16-18" barrel slinging 75-77's will handle just about anything target wise you'll find at a DMR match inside of 600 yards. Additional energy on target has its disadvantages in a match environment and sometimes competitors would tune their 6.5CM, 6.5 Grendel, .224Valk to the bleeding edge of reliability in an effort to soft recoil. It's all good when it's clean but sometimes it can cause them to malfunction later in the day when they were dirty.
There are some good insights in this thread:
Hey bpair what charge weight are you running with your 77SMK? Good looking setup there!!
www.snipershide.com
Because I like showing it, 5.56 16" SPR
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