What not to do.

[greentick]

BTDT lol. Get the collet.

 

[Dead Eye Dick]

ETA: Pull all your remaining loads and weigh the powder charge. Also, any chance you may have accidently put a different 30 cal bullet in round 4? Like maybe a 208gr Hornady BTHP?

This happens. Once, I found a .308 caliber bullet in a 500 box of .22 bullets. While this was easily notices, how un-noticeable would be say a .208 bullet in a package of .284 bullets, especially if the lengths were the same.

And, on a slightly related subject. I cleaned a quantity of range pickup brass. While looking over the box of fifty, I pulled one case. Though labeled as a 6.5 Creedmoor, it had been necked down to 6mm.

 

[Krichards]

So today I shit alittle bit..

(I've edited this after realizing my mistakes)

Was doing some load development. I have a bunch of CFE223 that I actually don't use for 223; but it was too cheap to pass up. So I'm using it for 308.

I looked around, found others recipes, found Hodgdon's data. I went off Hodgdon's data. Starting load is 45.5, max is 47.5

*this is where i fuck up*

Using FGMM brass*, wolf primers. Cases are full length sized with a .002 bump on shoulders. Hornady 178 BTHP COAL 2.86.

Started at 45.4 and did 5 rounds in .3 grain increments up to 46.9

The gun is a factory Remington 700P with a thousand or so rounds. At 46.6 on the 4th round I had powder or debris blow out the back of the bolt. Thankfully I wear glasses and just had my face peppered with what felt like dust.

Could not lift the bolt. So wacked it with a mallet. Could not pull the bolt back, so wacked it with a mallet. The case was stuck to the bolt. View attachment 7831291

Could not get the case off the bolt until I tapped it a bunch on the table.
View attachment 7831292View attachment 7831298View attachment 7831303
The primer went flying the moment I got the case unstuck from the bolt.


The flash hole seems to be twice the size of normal.View attachment 7831294

All the rounds prior had no sticky or even a little difficulty lifting the bolt.

The top two rounds in the next picture were 45.4 the two below were 46.6
I always get cratered primers on most non military primers. So I don't really use that as a sign of pressure. And the primers still have a radius. View attachment 7831297

So what happened?

I used to use CFE223 for my 308 gas gun with 175 SMK. 46.1 gr was where it started to indicate it was time to back down. They ran in my M700 OK but they were still a hot load. I never got anywhere near tearing up brass like your pictures show though. Even at 46.1, it was chronoed at 2615 out of the 16" barrel. Sure rang long range steel with authority. CFE is a good powder but seems to build pressure pretty fast. Glad all you beat up was some brass and a little pride.

 

[camocorvette]

CFE is a good powder but seems to build pressure pretty fast. Glad all you beat up was some brass and a little pride.

Thank you. I hope it works out. I've got a bunch of CFE. I just got complacent with a bit of stupid and lucked out. Next load development session with be better.

 

[OkieMike]

I used to use CFE223 for my 308 gas gun...

CFE is a good powder but seems to build pressure pretty fast.

Same for me. And I was running it in FC brass.

I have had more issues with CFE 223 than any other powder I've used. I'm not shit-talking it at all... But it seems to go from safe to unsafe pretty quick with only a minor increase in charge weight.

I think it's a good powder. But you better pay close attention when testing loads.

Mike

 

[camocorvette]

Same for me. And I was running it in FC brass.

I have had more issues with CFE 223 than any other powder I've used. I'm not shit-talking it at all... But it seems to go from safe to unsafe pretty quick with only a minor increase in charge weight.

I think it's a good powder. But you better pay close attention when testing loads.

Mike

Thank you. This is my first experience with it. My foolishness will make me be more cautious with all load development.

 

[Boogaloo]

My take on this is there is no way in hell that an over pressure event caused that flash hole to nearly perfectly, symmetrically, open itself up due to excess pressure, or even the blast furnace method of hot gasses reverting back through the flash hole during ignition. If it did, there would be clues like a ragged flash hole, or bell-mouthing of the hole itself. That (post event) flash hole is way too symmetrical for that to have occurred.

I'd place more weight on the possibility that you got a bad case, with a giant flash hole poked in it, it got past your QC efforts during the loading process, and the pressure of ignition blew the primer far enough back out of the pocket to let significant gasses escape rearward, into your face, and you got off easy.

I am happy to be wrong, because EVERY SINGLE TIME I am wrong, I am corrected by someone who is right, and I actually learn something new that day, which is my mission in life..