Blew a primer yesterday

[gerry]

First one in probably 20 years. Did some shooting with my 270 Win yesterday and one of the loads I tried was the 150 gr Speer Hot Cor with IMR 4955. I didn't notice any problems at the lower charges but when I fired my first round of 56 gr (less than Hodgdon's max with the 150 gr Hornady) I blew a primer. There was nothing unusual at all about the shot but the primer was gone which was quite surprising. The bolt lifted easily and there was no ejector mark on the case either. It was a brand new (but old stock) Hornady case and a Federal 215 primer. I'm not sure if this was just a faulty case or if I was indeed running a high pressure load. I'm going to regroup and try some Winchester cases and work up again and see what happens. I didn't use the chronograph last time but will this next time out to see what the speed actually is.

 

[5shot]

Strange you could lift the bolt so easily.

Sent from my XT1585 using Tapatalk

 

[gerry]

It was strange, nothing seemed odd about it at all till I saw the primer was gone on the case.

 

[truck driver]

I had one pierce the shoulder with a below max load in my 7mmRem but not a complete blow out.
Did you measure the primer pocket to see if it was over size or could it have been an under size primer cup?

 

[TackDriver284]

When seating the primers, did it feel snug?

I had the same issue with the Fed 215M with the .300 Win Mag a few weeks ago, pitted the boltface. No heavy bolt lift and was a grain or so under max too. Primer just leaked. Did not look like it had pressure since primer edges are rounded. Primers were tight when seating.

 

[gerry]

I can push the primer back into the case. It measures bigger than another spent primer I just checked. I never noticed any problems seating the primers when priming the cases originally.

The bolt face is pitted too now unfortunately :x

 

[kraky1]

Do you use a hand primer? I got my first one many many years ago and I really like how much feedback I get from it as I seat the primers versus The Press. It might be possible there was a mismatch in the fit or a defect in the primer pocket of the brass...or...any chance your scale hung up or malfunctioned for one round....?
Just some other ideas. With all the trouble people have had with Winchester primers a bolt face with a pit is no longer unusual and that goes for a couple of my rifles....lol!