Got brass troubles. Cause ? Video posted

[dantiff2]

I contacted Starline to see if there are any recalls. Waiting to hear back.

 

[fkimble@charter.net]

The cut open cases show what looks like the end of the annealing at the exact location of the split/separation line. I'd call Starline. They would probably line a few cases to examine.

Frank

 

[DLT]

You can adjust for length, but not width. What is the diameter at the base above the extraction groove vs. the old chamber? Where is the barrel from?

Unknown but low round count on win brass measures .374

4 firing starline brass .375

 

[AlNyhus]

Oh yea have had for a couple years now. Fired measures 1.450. Sized 1.449 - 1.448

Great.

Now, check some of the new brass you have. -Al

 

[DLT]

Great.

Now, check some of the new brass you have. -Al

I brought one new starline piece with me to work it measures .374

 

[DLT]

I brought one new starline piece with me to work it measures .374

No I don’t have my tools here to measure the headspace here at work. I did set the barrel up at bare minimum Go gauge with 1 piece of scotch tape on back of it.

 

[whatsupdoc]

I had 100 223 lapua cases that were fired 12 times, the primer pockets got a little loose
so I retired them. The rifle's headspace was set intentionally tight to match new lapua brass.

I bought 500 pieces of 223 Starline brass, lost like 5 out of 100 due to case separation
in the same exact spot as the OP with around 9 firings bumping .002. Retired them and loaded 50 cases and bumped only .001 each time and had one case separate in the EXACT SAME SPOT as the OP after 7 firings.

 

[LHSmith]

I brought one new starline piece with me to work it measures .374

Caliper or micrometer measurement? I have measured some of my .223 and 6x 45 brass fired in bolt guns and the fired brass all measures low to mid .374. Your new chamber may be bigger at the back end. A mic measurement would be better.

 

[DLT]

I had 100 223 lapua cases that were fired 12 times, the primer pockets got a little loose
so I retired them. The rifle's headspace was set intentionally tight to match new lapua brass.

I bought 500 pieces of 223 Starline brass, lost like 5 out of 100 due to case separation
in the same exact spot as the OP with around 9 firings bumping .002. Retired them and loaded 50 cases and bumped only .001 each time and had one case separate in the EXACT SAME SPOT as the OP after 7 firings.

If that’s the case my batch is way worse off than yours. I went through them this morning. 94 has the obvious line around the body. Only 6 didn’t that I could see. These was run on the upper end of published load data. But I couldn’t see or find any signs of pressure in my rifle

 

[DLT]

Caliper or micrometer measurement? I have measured some of my .223 and 6x 45 brass fired in bolt guns and the fired brass all measures low to mid .374. Your new chamber may be bigger at the back end. A mic measurement would be better.

Using mics. I got the same using calipers.

 

[dantiff2]

I had 100 223 lapua cases that were fired 12 times, the primer pockets got a little loose
so I retired them. The rifle's headspace was set intentionally tight to match new lapua brass.

I bought 500 pieces of 223 Starline brass, lost like 5 out of 100 due to case separation
in the same exact spot as the OP with around 9 firings bumping .002. Retired them and loaded 50 cases and bumped only .001 each time and had one case separate in the EXACT SAME SPOT as the OP after 7 firings.

Sounds like an obvious manufacturing issue. I've gotten 20+ loads on Win and LC 223 brass. Wouldn't expect any less from this brand. Can't see annealing being an issue either cause I over anneal compared to most guys and have never had a separation issue.
Dan

 

[DLT]

Sounds like an obvious manufacturing issue. I've gotten 20+ loads on Win and LC 223 brass. Wouldn't expect any less from this brand. Can't see annealing being an issue either cause I over anneal compared to most guys and have never had a separation issue.
Dan

I’m about to be on that train also. When I size these cases it’s not much effort at all. I have sized cases fired from different rifles which must have had fatter chambers from the effort I had to put on the handle. I guess I can swap brass brands and see what happens

 

[Webster]

View attachment 1423069View attachment 1423070

I had a case separate today which was a first. It’s starline brass bumped back 2-3 thou depending on what day it is, and this was the 4th firing. Many out of the 100 I started with shows a faint line outside on the body where it snapped. Anyways I anneal after every firing. 223 cases. I have seen ( not through personal experiences) the case head separate from over sizing and I have had split necks and I have had primers get blown out but not so much this. Helps. +++EDIT+++ I’ll also add I can not feel anything inside the cases where the line is forming with a paper clip. 94 out of the 100 has the obvious line around the outside of the case. 6 doesn’tView attachment 1423205

I would dump the brass buy another brand. Back off on the powder charge. Get all the sizing lube off the case. Don't have a clue. Eliminate some possibilities. Sounds like everyone on this website wants to push the limits. I thought separation normally occurred near the case head. The back of the cartridge is not in the chamber. The extraction grove has to be outside the chamber. That’s why swelling occurs at the .200” line. Over annealing not possible. If it was the case would stretch with more elasticity and resist cracking. Work hardening increases the likelihood of cracking. Soft stretches without cracking. Been reloading since 1970 never had a case separation. Always though it was weird that the work hardening that resulted in cracking occurred in such a narrow space. If I was still working it would be interesting to do a metallographic cross section across the crack and see the appearance of the work hardening by looking at elongated grains. A micro hardness profile across the crack should be done. Maybe this is something AMPS could do so we could learn something.

 

[markm87]

I'd be backing that die off until the brass started to get snug in the chamber. I don't need no stinkin instruments to solve this one. I set my dies up cave man style!

 

[DLT]

I'd be backing that die off until the brass started to get snug in the chamber. I don't need no stinkin instruments to solve this one. I set my dies up cave man style!

Like I said. Or if I didn’t I’m about to, I’m so close to .002 bump it’s scary. Some cases come out .001 some at .003 I sure that’s way less than many around the world

 

[Bill K]

why bump the shoulder back each time you resize ? Just touch it, as it is forming to fit your chamber and really does not need set back unless it starts getting very hard to chamber.
Try that with about three of your cases and see if your issued stops and you get a few more reloads out of those cases until they do close with more effort.

 

[DLT]

Great.

Now, check some of the new brass you have. -Al

Here is some measurements from a bushing I had at work. New is 1.456. Fired 1.460 AGAIN this is not from my tool at the house

 

[K22]

why bump the shoulder back each time you resize ? Just touch it, as it is forming to fit your chamber and really does not need set back unless it starts getting very hard to chamber.
Try that with about three of your cases and see if your issued stops and you get a few more reloads out of those cases until they do close with more effort.

This ^^^^, plus,

Dump the affected lot of brass - it ain't worth the risk.

However, with the small bump reported, if accurate, that shouldn't in itself cause a separation. My first guess is that the metallurgy of the brass is off.

I don't anneal so I know nothing about it however could that possibly cause or accelerate the fatigue of the case? Those who anneal should be able to answer that question.

 

[HartwickCo]

View attachment 1423069View attachment 1423070

I had a case separate today which was a first. It’s starline brass bumped back 2-3 thou depending on what day it is, and this was the 4th firing. Many out of the 100 I started with shows a faint line outside on the body where it snapped. Anyways I anneal after every firing. 223 cases. I have seen ( not through personal experiences) the case head separate from over sizing and I have had split necks and I have had primers get blown out but not so much this. Helps. +++EDIT+++ I’ll also add I can not feel anything inside the cases where the line is forming with a paper clip. 94 out of the 100 has the obvious line around the outside of the case. 6 doesn’tView attachment 1423205

Apologies if you've already mentioned this, but how did you cut the cases for such a perfect cross-section?

 

[Ringostar]

why bump the shoulder back each time you resize ? Just touch it, as it is forming to fit your chamber and really does not need set back unless it starts getting very hard to chamber.
Try that with about three of your cases and see if your issued stops and you get a few more reloads out of those cases until they do close with more effort.

YES! He said that he’s bumping 0.002-0.003 from a free bolt fall. If the bolt closes cleanly, there’s no reason to push back any farther.