6 br brass problem

[remdriver]

Has anyone had this problem or seen it.
Lapua 6mm br brass. Any help would be appreciated

 

[gunsandgunsmithing]

Has anyone had this problem or seen it.
Lapua 6mm br brass. Any help would be appreciated

I don't think you have a brass problem. Possibly too much unsupported case but I don't think so. What's the load and were there other pressure signs, like heavy bolt lift? It looks like massive over pressure Either way, stop shooting it until you figure that one out!

 

[remdriver]

it was 30.2 grains of varget with cci450 2.391 overall lenght

 

[gunsandgunsmithing]

it was 30.2 grains of varget with cci450 2.391 overall lenght

Bullet? Even for a 105ish, it sounds warm but not THAT hot. Sure looks like huge pressure, for whatever reason. Too much unsupported case would look similar but based on the "belt", it's close to where it should be...maybe a tad too deep but close. What action, too?

 

[Tesoro]

Maybe the bullet is .257 ?!!

 

[remdriver]

This belongs to a frind of mine,but it's an impact action. He had two do this in a match. It has 3 firings on it and is annealed after each firing on a amp annealer. I wonder if maybe he over annealed it. He switch to Norma brass and has'nt had a problem so far. I think he is shooting Berger 107's

 

[Straightshooter1]

This belongs to a frind of mine,but it's an impact action. He had two do this in a match. It has 3 firings on it and is annealed after each firing on a amp annealer. I wonder if maybe he over annealed it. He switch to Norma brass and has'nt had a problem so far. I think he is shooting Berger 107's

Because of the way the AMP annealer works, it's NOT likely an annealing problem. . . even if it was "over annealed". The AMP heats up the neck and shoulder really hot, really fast and for such a short time that very little of that heat gets down to that part of the case and the brass cools off pretty fast. So, I'd say something else is going on.

 

[Bulletman]

Show us pictures of his fired brass that DID NOT blow out like these. If you can please.

 

[gunsandgunsmithing]

This belongs to a frind of mine,but it's an impact action. He had two do this in a match. It has 3 firings on it and is annealed after each firing on a amp annealer. I wonder if maybe he over annealed it. He switch to Norma brass and has'nt had a problem so far. I think he is shooting Berger 107's

As for now, I'd say he had two over charged cases. That's almost certainly a way over pressure situation for some reason.

 

[swd]

Wow! By the ring in the brass it appears that it starts at the edge of the unsupported back of the chamber. It’s more unsupported case than I would do by not by a lot. I would put in a call to Lapua. I’m sure they would like to see this.

 

[remdriver]

I'll try to get some pitcures of the brass, but he hes cleaned and sized it. He gave it to me,but I have'nt had a chance to pick it up. I sure would hate to have to trash 350 Lapua brass as hard as they are to come by in 6 br

 

[rwj]

I’m not familiar with an Impact action, but it appears that the extractor is creating a circular ring/scratch on the case above the extractor groove. The scratch can be a initiation point for a stress crack in this unsupported area.

 

[moondog]

Why do the cut aways look like 2 different brass manufacturers

 

[M-61]

This belongs to a frind of mine,but it's an impact action. He had two do this in a match. It has 3 firings on it and is annealed after each firing on a amp annealer. I wonder if maybe he over annealed it. He switch to Norma brass and has'nt had a problem so far. I think he is shooting Berger 107's

Too little info and it’s third hand.
“” over annealed” you mean he might had the case head glowing.
Really impressive that he kept shooting too.

 

[ChrisNZ]

"Impressive' is not the word I'd be using..

I'd suspect he's waaay out of his depth and needs skilled assistance.

 

[remdriver]

Too little info and it’s third hand.
“” over annealed” you mean he might had the case head glowing.
Really impressive that he kept shooting too.

That is what I was talking about and he stopped after #2.

 

[remdriver]

He gave me the brass,350 pieces. That's why I was asking here. I do want to inspect it,but I don't think I'll chance useing it. I want to thank everyone that has replied. You've all been a big help.

 

[Fast14riot]

I've seen something like this with an out of battery discharge on a semi, but not sure how you could do that on a bolt gun and not have the bolt embedded in your face.

 

[J.J. Coe]

By the looks of the ring next to the extractor groove I'd say a little to much unsupported case isn't helping. I'd be doing some measuring.
On a side note, my br chambers support the body all the way to the extractor groove with .010 bolt nose clearance.

 

[JFrank]

Those certainly appear to be of separate manufactures.

Why do the cut aways look like 2 different brass manufacturers