@Ds J - please send me a WhatsApp - my phone was stolen and I have lost your number.

I would suggest the following :-
1. Use the existing charge but load with a COL that jams in the lands - QL calculates a pressure of 52K psi for doing that. That should be enough to fireform properly.
2. Anneal 3 cases so that the shoulder is also affected - do this after resizing.
3. You now have a softer font part that can stretch forward.
4. Measure the case lengths after shooting. If there is excessive head space those measurements should show it.

Photos to come.

The cases have not been loaded much - less than five times, and mostly with decent loads for practice.

And I am pretty sure that it occurred with one 168gr load and the same cases.

At one stage I thought it could be magnum primers (I mentioned it on this forum) but that was eliminated.

6 x masking tape is HUGE head space !, 1 x packing tape, the thin thin one, usually brown in color is usually used to measure this distance non professionally.
6 x masking tape is like worse than most bad .303 are.
I do not want to argue with janfred, but ?? I would blame head space for blown primers.

Next is I would have the barrel set back to rectify.

Blown primers can also result from cases with issues, I get it often when testing beyond max loads and then reload that case - the primer pockets stretch from ++ pressures. 

I would also test to see if this happens across the board with different reloaded cases from different batch's and loads.
 

Quote from: Treeman on May 01, 2024, 07:53 PM**************
The GunSite ban love affair is long standing.
 Fuck em !
When that false friend KK guy did his play up to me with that human horror Big T, the cause was good, get rid of a absolute cunt, the reasons only came out later when I stopped dancing to his commands. That whole GS is a little powerplay with the Superior Beings being the moderators. I must say however there are mods like Cammo that just moderate, no superior being perceptions.
             thought I would battle without GS, but I still have most of the guys on all other media.

The 2 you mention pretty much killed that site.  On the odd occasion that the site isn't down these days, it's just the same handful of people still posting.

The articles on the front page must be close to 10 years old now.

Well, blown primers are usually not a headspace problem unless it is mm's to large. If your firing pin can set off the primer, it shouldn't blow the primer.

Can you place a photo of one of the blown primers?

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Good morning Folks!

When does headspacing turn into a problem?

I have had three or four blown out primers in my 308 over the last year or two. Some readers might remember that I asked about it on other forums.

A month ago, when I was sure all possible causes had been checked and fixed, it happened again that the recoil felt funny, the bolt was stuck and the primer blew out.

Yesterday we determined that the headspacing was too much. The bolt closed stiffly with six patches of masking tape on the back of the case. I also have a small recess on the face of the bolt.

The basics of the rifle and load:

BRNO ZKK601 in 308
PMP cases
CCI primers
36.5gr S335
Hornady 180gr SST
2330fps
1.75mm jump

Any ideas or comments on fixing this?

I have hearf several suggestions:
- fire forming cases
- cutting the barrel and chamber
- replacing the barrel completely

Quote from: Pierrevw on Apr 29, 2024, 06:19 PMMy first buffalo hunt

**************************************
Your buff really is a nice one, some are decidedly ugly brutes and yet others just seem more "good looking". A kid I taught to hunt recently shot a big buff  intruder on their farm - using a .308 and 180gr Norma Oryx bullets. His buff was one of those sparsely haired dandruff grey buff.
This one seems so beautifully unmarred.