I went to the the rifle range a couple weeks ago to make a few test shots and verify my scope was still on Zero as I had a rifle hunt to make last weekend.
I was acting range officer while I was there. As I was waiting on my barrel to cool down between shots a group of three guys and two women came and set up beside me.
I called the range cold so they could put a few targets at the 100 yd berm.
Once they set up and I called the range hot again, I noticed they were shooting three different rifles from two benches. One of the first things that disturbed me was I heard one of the guys say to one of the others "Hey you shot my target instead of yours".
What really disturbed me was the two guys shooting different rifles from the same bench is when one said "What Happened?"
He had a fail to extract. They knocked the case out of the chamber with a cleaning rod, then I heard one say, you blew the primer.
I decided that I'd better see what was going on.
As I was approaching their bench, sure enough, I saw a spent primer laying beside their rest.
I picked up the primer, examined it and noticed it appeared to have a very hard firing pin strike to almost rupture.
The guys were looking at the case and another case fired from the same rifle.
I told them to hand me the cases.
Instantly I saw the problem. They had fired a 6.5 creedmoor in a Win 308 rifle. I looked on their bench and sure enough, there was a box of 6.5 CM and 308 Win sitting next to each other.
As acting RO I commenced to chewing butt for having the two different caliber ammo sitting next to each other on the bench and for general stupidity of not paying attention to what they were doing.
I then delegated my RO duties to another shooter, packed up my gear and left.