Case head separation on a factory reload: next steps?

[CJ]

A few years ago, I bought some 9mm FMJ 124gr. 'factory' reloads at a show in California

I've shot hundreds of the things since then with no problems...until yesterday. Shooting a Hi-Point carbine, one round sounded funny, and I felt a little puff of stinky smoke blow over my hand, and wafting out of just about every opening for a few seconds. After a quick inspection, I continued the session.

Later while sweeping brass, I discovered the blown-out tube of the case, and a short search later, found the head. What were the most likely causes of this? A weak case? Possible firing out of battery (can a HP Carbine do that?)?

So my question is...what do I do with the rest of this stuff? Pull it, dump the powder and reload it? Pull and measure the powder for each load and reload with the same powder? Keep shooting the last few hundred rounds since it's only been one failure in about 700-800 rounds?

I appreciate advice from those more knowledgeable than me

 

[rcmodel]

I discovered the blown-out tube of the case,

A photo would help, but if you mean truly "blown-out", with the head gone, that can only happen out of battery.

A complete case seperation with a straight-wall pistol case is a very rare bird.

Inspect the other cases and see if you are getting a bulge where the feed ramp would be.

If so, it may have just been a weak case in an unsupported chamber.

But if the whole front of the case is blown out, it had to have fired out of battery.

rcmodel

 

[CJ]

Thanks rcmodel, great to know. We're talking complete separation here, a nice neat (well, as neat as a cut via expanding gas could be) separation where I found the tube of the brass, then had to hunt for the head. I'll work on pictures if they'd help (I saved it to put on my up-and-coming reloading workbench as a reminder of the power involved in reloading), but from what you've said (and how the carbine was behaving), I'm guessing it was slightly out of battery.