Calling all gunsmiths

[Danny1788]

So I am full length sizing and bumping the shoulder back .002-.003.

I'm with rfurman24 on this one. All your measurements seem fine. Nothing is jumping out as an issue. Without the rifle in hand to inspect, the interweb is gonna send you down a rabbit hole. Take it to a smith and let someone with hands on knowledge find the issue. People will just guess about what's wrong with it.

 

[25WSM]

If you inspect the inside of the case and find nothing. I would borescope the chamber. The reamer can get a burr on it and leave a slight gouge depressed into the chamber. Can also leave a slightly raised up ridge along the gouge. Normally happens on a brand new reamer. I have nothing else to tell you. Every gun brought to my shop with this issue was headspace related. I did just recently work up loads for a 7mag. I set up the dies to bump the shoulder .003 and was shooting 180vld at 2825fps with h-1000. Not even close to max. Had cases cracking in 3 shots. This was Hornady bulk brass. Nothing out of spec on this one either. Good luck in your search. Let us know when you find the culprit. That's how we all learn more. After 30 years smithing I still see stuff that defies all logic. Shep

 

[nicholasjohn]

If you inspect the inside of the case and find nothing. I would borescope the chamber. The reamer can get a burr on it and leave a slight gouge depressed into the chamber. Can also leave a slightly raised up ridge along the gouge. Normally happens on a brand new reamer. I have nothing else to tell you. Every gun brought to my shop with this issue was headspace related. I did just recently work up loads for a 7mag. I set up the dies to bump the shoulder .003 and was shooting 180vld at 2825fps with h-1000. Not even close to max. Had cases cracking in 3 shots. This was Hornady bulk brass. Nothing out of spec on this one either. Good luck in your search. Let us know when you find the culprit. That's how we all learn more. After 30 years smithing I still see stuff that defies all logic. Shep

Did you happen to measure where the shoulders were on the new factory brass ? I had this happen, too. They were stretching enough to crack on the very first firing. It seems to me that this could only have happened if the case was too short at the shoulder, AND had a belt that was not the correct dimension. I suppose that if they could get one dimension wrong, they could probably also screw up the other as well. Is there anything else that you can think of that would cause this to occur ???

 

[PPR]

I would be searching for some brass with a bigger back end. You may be surprised how much variance there is from brand to brand. Had a .22-250 like this year's ago and Federal brass fixed the issue.

Paul

 

[nicholasjohn]

I would be searching for some brass with a bigger back end. You may be surprised how much variance there is from brand to brand. Had a .22-250 like this year's ago and Federal brass fixed the issue.

Paul

Good call, Sir. If you have min-spec brass in a max-spec chamber, this might be the end result.

 

[Nomad8961]

I'd buy some factory ammo, shoot it and send the fired ammo and box to Bergara. That might help them realize the chamber is over sized

 

[IdahoCTD]

What I would do is expand the case necks on a few rounds of brass to 8mm or 338 and then run it back through a FL die until the bolt just closes with some resistence. That will create a false shoulder to tighten the headspace and not allow the brass to blow forward and out. It will just allow it to go out. If it doesnt split or crack after that then it means your brass is short or your chamber is long. Brass being .007-.008 under chamber size at the back is pretty common, especially with older cases.