Primer pockets blowing-300 blk out

[tiller]

Never had a problem with this before...

Never blown a primer pocket at all, let alone with 223...

All brass is formed from 223 cases...

What would be causing this....?

[freonr22]

Pics ?

[tiller]

[tiller]

I don't see any signs of over pressure in the necks...

This was 2 different loads.. Had about 6or 7 out of 100 rounds

[rix]

My guess is, loose primer pockets. Although it takes time I like to seat primers by hand. you get a much better feel for the loose pockets.

[freebug]

Is your case length correct? If it's too long or short, it may not full chamber and when you fire the bolt face isn't flush with the back of the case causing primer blow out. Grab some of the ones that aren't bulging out and measure.

Was the overall length correct?

[klewan]

The second and fourth ones have brass flow into the extractor hole; those are pretty damn hot. What powder, how much, what bullets did you use?

[tiller]

The second and fourth ones have brass flow into the extractor hole; those are pretty damn hot. What powder, how much, what bullets did you use?

Loads were 150 hornady sp
Wolf 223 primer and medium load of 15.7 grains of ramshot enforcer.


The max load listed was 16.8


Other load 165 grain hpbt
Wolf 223 primer with 14.5 grains of ramshot enforcer

None of these were hot

[tiller]

Is your case length correct? If it's too long or short, it may not full chamber and when you fire the bolt face isn't flush with the back of the case causing primer blow out. Grab some of the ones that aren't bulging out and measure.

Was the overall length correct?

Trimmed too 1.358 with a variance of .003 either way

I think saami spec is 1.348-1.368

[tiller]

My guess is, loose primer pockets. Although it takes time I like to seat primers by hand. you get a much better feel for the loose pockets.

It was range pick up... But I don't have time to prime by hand... Nor do I have a hand primer to do so

[Ferrum]

Kind of looks like over pressure to me? Primers are blown out, and it was blown back hard enough to put the face of the bolt on the base of your brass...

If you have any left over, I'd pull bullets and QC them.

[Ferrum]

Trimmed too 1.358 with a variance of .003 either way

I think saami spec is 1.348-1.368

The Hornady Manual has a case length of 1.390 with max at 1.40?

[Ferrum]

Loads were 150 hornady sp
Wolf 223 primer and medium load of 15.7 grains of ramshot enforcer.


The max load listed was 16.8


Other load 165 grain hpbt
Wolf 223 primer with 14.5 grains of ramshot enforcer

None of these were hot

One other thing... The Hornady manual does not list Enforcer, but does list Accurate No 9 (right next to each other on burn rate chart). Hornady only shows Accurate No 9 going to 13.1 grains.

Hope this helps.

[tiller]

http://www.accuratepowder.com/wp-content/uploads/2010/09/300_ACC_Blackout_Data.pdf

Here is where I got my data from... Straight from accurate....

And there could not have been any more qc... I used an rcbs charge master for each round...

All brass was sized correctly with a Wilson case gauge...

Also I pulled my trim length from ar 15.com... All those guys over there said trim length was 1.358 and that's what there trimming too... About 20 guys use that with no issue.


Also I think the fourth post states that hornadys manual was a misprint... I've heard this many times before too

http://www.ar15.com/forums/t_6_42/385765_300_Blackout_Master_Thread.html

[G-forceJunkie]

Holy crap those are over pressure. You got the case flowing back into the ejector hole. Stop. Right now. Reevaluate your load.