Weird Ring

[Black Hat]

That brass is on verge of separating, a wonder it hasn't already. Just look at case on left, by enlarging, bet you can stick a pin thru it.

Dump it, it's dangerous!

That's exactly what I thought, I wouldn't be concerned about the other ring down the case, the head appears almost separated.

 

[Nunu]

It's a 308 win Lapua brass fired 3 or 4 times. The head grew up 1.5 to 2 thousandth from its brand new length and was resized around 2 thousandth of an inch every time. Below are some of the cases having partial rings on them.View attachment 261200View attachment 261200

Correction, I mean the shoulder grew up not the head after shooting the brand new brass. Sorry about that.

 

[Nunu]

That brass is on verge of separating, a wonder it hasn't already. Just look at case on left, by enlarging, bet you can stick a pin thru it.

Dump it, it's dangerous!

I will, no intention of using it again just curious, never see this before. Thanks.

 

[Black Hat]

There must be a head space issue for only 4th firing, it looks like its had 10+ heavy loads through them.
I have seen similar sings on my .303 cases but they are renowned for excessive headspace, even using an oring on the rim your lucky to get 4 firings.
Have you measured how much the case body expands from sized to fired.
What load are you running?

 

[Nunu]

There must be a head space issue for only 4th firing, it looks like its had 10+ heavy loads through them.
I have seen similar sings on my .303 cases but they are renowned for excessive headspace, even using an oring on the rim your lucky to get 4 firings.
Have you measured how much the case body expands from sized to fired.
What load are you running?

Yes, almost nothing, around 1.5 to 2 thousand.

 

[Laelkhunter]

If you can fire some factory loaded ammo through the rifle, and compare the cases, then post photos of the fired cases of the factory loads.

 

[Critter Picker]

Looks like case head separation to me.

 

[PApa Black]

It's a 308 win Lapua brass fired 3 or 4 times. The head grew up 1.5 to 2 thousandth from its brand new length and was resized around 2 thousandth of an inch every time. Below are some of the cases having partial rings on them.View attachment 261200View attachment 261200

I use LC brass in my 308 and after 10-12 resizings they look like the case on the right: about to separate. I can feel the crack with a dental pick.

 

[slikmrc]

Those cases are a hot mess! It looks like most of rings are in three areas of the case. I would cut a couple of those cases in half and see if there is wall thinning.

 

[Nunu]

Those cases are a hot mess! It looks like most of rings are in three areas of the case. I would cut a couple of those cases in half and see if there is wall thinning.

I was about to do exactly what you but had another thought. I was using a very sharp needle if I can feel the the line but I can't, so I decided to clean it with a brass compound and here's the result: the ring is now totally gone
I will shoot factory some ammo and new brass reloads to further verify what the heck is going on here and will cut some of the ring-etched brass. I'll let you guys know.

 

[nmbarta]

That's exactly what I thought, I wouldn't be concerned about the other ring down the case, the head appears almost separated.

The head of the case, is where the letters/numbers are, not where you circled the case. Case head separation usually happens where the web meets the case wall. Based on what I'm seeing I would guess you have a chamber issue, but your not running your load too hot (which would be good) and your brass is not flowing into the flaw in your chamber, but there is some carbon that builds in those spots. There is also a ring where the neck meets the shoulder, all of the rings are consistently placed on the brass. This indicates that it is not a brass issue, but a chamber issue. From what you've described, you don't have a headspace problem. I've been wrong plenty of times, but I'd bet on chamber problems, lapua brass is tough and can hide pressure issues. Just like ejector marks, you shouldn't see them until your brass hits the point that it starts to "flow". Your brass, shouldn't "flow" into those small flaws until you get to your max (or really just past your max) load. The marks are too perfect, and too consistent to be anything else imo. Case head separation in multiple cases will happen in "about" the same spot, but it doesn't look like that.
When I zoom in on your picture, I can see that your chamber is a bit rough. I can see rings that parallel the obvious ones, this is consistent with machining problems. It might be minor enough to have it polished out. Hard to tell from here.
Good luck with it, keep asking questions.

 

[Nunu]

The head of the case, is where the letters/numbers are, not where you circled the case. Case head separation usually happens where the web meets the case wall. Based on what I'm seeing I would guess you have a chamber issue, but your not running your load too hot (which would be good) and your brass is not flowing into the flaw in your chamber, but there is some carbon that builds in those spots. There is also a ring where the neck meets the shoulder, all of the rings are consistently placed on the brass. This indicates that it is not a brass issue, but a chamber issue. From what you've described, you don't have a headspace problem. I've been wrong plenty of times, but I'd bet on chamber problems, lapua brass is tough and can hide pressure issues. Just like ejector marks, you shouldn't see them until your brass hits the point that it starts to "flow". Your brass, shouldn't "flow" into those small flaws until you get to your max (or really just past your max) load. The marks are too perfect, and too consistent to be anything else imo. Case head separation in multiple cases will happen in "about" the same spot, but it doesn't look like that.
When I zoom in on your picture, I can see that your chamber is a bit rough. I can see rings that parallel the obvious ones, this is consistent with machining problems. It might be minor enough to have it polished out. Hard to tell from here.
Good luck with it, keep asking questions.

Yes, I agree if we are talking only about a rifle. However, what really puzzled me is we collected cases from four (4) different rifles and they all have similar rings but located on different spots. Two of them are factory 308s (Rugger Precision and Remington 5R Mil Spec), a 308 tube gun chambered by Jim Borden and a 6.5x47 Lapua chambered by Impact Precision. If it's only one rifle it will be much easier for me. Additionally, each rifle have dedicated semi custom sizing die. The only common factor I can think off is, they all are Forster die. I'm sending the dies to Forster for polishing just to rule out dies. Thanks.

 

[slikmrc]

With it being four different rifles, think I would look at brass prep. Do they go into the cleaner with marks on them? If you can't feel a ridge with a pick and you can clean off marks it looks like some kind of tarnish issue or chemical reaction.

 

[Nunu]

The head of the case, is where the letters/numbers are, not where you circled the case. Case head separation usually happens where the web meets the case wall. Based on what I'm seeing I would guess you have a chamber issue, but your not running your load too hot (which would be good) and your brass is not flowing into the flaw in your chamber, but there is some carbon that builds in those spots. There is also a ring where the neck meets the shoulder, all of the rings are consistently placed on the brass. This indicates that it is not a brass issue, but a chamber issue. From what you've described, you don't have a headspace problem. I've been wrong plenty of times, but I'd bet on chamber problems, lapua brass is tough and can hide pressure issues. Just like ejector marks, you shouldn't see them until your brass hits the point that it starts to "flow". Your brass, shouldn't "flow" into those small flaws until you get to your max (or really just past your max) load. The marks are too perfect, and too consistent to be anything else imo. Case head separation in multiple cases will happen in "about" the same spot, but it doesn't look like that.
When I zoom in on your picture, I can see that your chamber is a bit rough. I can see rings that parallel the obvious ones, this is consistent with machining problems. It might be minor enough to have it polished out. Hard to tell from here.
Good luck with it, keep asking questions.

Yes, I agree if we are talking only about a rifle. However, what puzzlesme is

With it being four different rifles, think I would look at brass prep. Do they go into the cleaner with marks on them? If you can't feel a ridge with a pick and you can clean off marks it looks like some kind of tarnish issue or chemical reaction.

I'm also thinking of that. We didn't check it the last time. We will be shooting new brass and factory ammo. I'll let you know. Thanks.