Ring on brass as case head failure indicator

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Novice reloader, was sorting brass and noticed my 2x fired Norma brass has a ring around the case where 1x fired (first firing was factory loaded) doesn't have the ring. My load is book max but shows no pressure signs. Cases are FL sized

Is that ring always an indication of case head failure? I was suprised to see it after 2 firings. Any way to tell if it's actually separating? I've heard of the paperclip truck bit what exactly am I feeling for? Any help is appreciated.
 

Pdog06

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If you have a borescope, or access to one, look at the same location on the inside of the case. If it’s too hot of a load then there should be something there. If not then check the bore for burrs or something?
Surprised it would be a pressure issue with no other signs of pressure though.
I definitely wouldn’t use that brass again till you figure it out though.
 
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Meant to post a pic with the original post, sorry. 1x on left, 2x on right20230918_051642.jpg
 
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looks to me like the resizing die isn't making contact all the way down (normal). do you know how much you're bumping the shoulder back each time?

with a paper clip you're feeling for a divot/crack/ravine/gouge. a borescope will also show it to you, or you can sacrfice a case to the hacksaw/dremel and cut to see if there is any thinning in that area.
 
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looks to me like the resizing die isn't making contact all the way down (normal). do you know how much you're bumping the shoulder back each time?

with a paper clip you're feeling for a divot/crack/ravine/gouge. a borescope will also show it to you, or you can sacrfice a case to the hacksaw/dremel and cut to see if there is any thinning in that area.
I see the color variation where the die isn't making contact on the brass base, but above that there is a faint ring above that 1/4" or so. It's a bit darker in color than the rest of the brass.

I'm not sure how far the shoulder is getting bumped. I'll have to look up how to do that. I just full length size everything for now.

I will see if I can feel anything like you describe with a paper clip and if I have to, I'll cut one open.
 
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Bolt lift is normal, no brass swipe marks on headstamp, primers not flattened, no excessive primer flow around where firing pin contacted primer.
 

Dos XX

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Bend the end of a paper clip and stick in the case to see if you can feel anything inside the case in that area.

Is that where the hole in your ammo box contacts the case?
 

wapitibob

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Setting a fl sizer per the paper instructions is a sure way to bump your shoulders back over .010.
It is unlikely that a single firing will fully form your brass, I don’t fl size until 2x fired.
To check your die without a comparator you can run the 2x fired brass shoulder thru a wax candle flame to create a thin soot layer and set your die to just touch that soot. When you get a comparator, you can then measure the 3x fired shoulder to case head dim and know where you are at and bump from there.
You want the fl die to hit the shell holder so there is consistent cam over and stroke length but you can bum the shoulder back too far. To fix that, competition shell holders are used to lower the brass deeper inside the holder and result in less shoulder bump while still allowing the die to contact the upper face of the shell holder. The comp holders will allow up to .010 less bump.
 
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I checked the ammo box theory, but the lines don't match up. I felt all the cases with a sharpened and bent paperclip, did not noticed anything with that method. I have no idea, I will load a few of them and see if it gets worse or more noticeable on the next firing.

I will also look into the shoulder bumping thing. I figured I'd always full length size to keep things simple, but I can see why you don't always want to be doing that.
 

letrbuck

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Bend the end of a paper clip and stick in the case to see if you can feel anything inside the case in that area.

Is that where the hole in your ammo box contacts the case?


Exactly what I do as well. I get a bit of that type of ring from factory federal rounds in two different rifles, doesn't mean you're edging towards case head separation, but you'd be able to feel it if you were
 

Novashooter

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I checked the ammo box theory, but the lines don't match up. I felt all the cases with a sharpened and bent paperclip, did not noticed anything with that method. I have no idea, I will load a few of them and see if it gets worse or more noticeable on the next firing.

I will also look into the shoulder bumping thing. I figured I'd always full length size to keep things simple, but I can see why you don't always want to be doing that.

There is nothing wrong in that picture. That is a perfectly normal thing, that's just how your sizer hits the brass. Do not worry about it.

There's lots of opinions on sizing brass, and even more methods on how to get there. Full length sizing every time is a perfectly acceptable method of doing it, and by far the most common. What Wapitibob is saying is that brass doesn't always form completely to your chamber. If it did, you wouldn't be able to extract it. By firing 2 times without body sizing you are expanding that case body closer to your chamber size. You can run into issues with this method though, one being you might not be able to chamber your rounds. This depends on your brass, how hot your loads were, etc.

If you measure a handful of cases for headspace (being sure the primer isn't effecting your reading), you will find they will vary in that base to datum measurement. This is normal, and happens from variation in brass spring back. What I do is use a number on the higher end, and use that for my reference. I will then normally size to bump that shoulder back .002" to .003" ideally. Many shoot for less, but this is the range that works for me. If you are shooting for that minimal .001" bump, you will probably find you need to anneal your cases. The variation in your brass hardness will make it very hard to keep your headspace variation case to case that low without annealing. Even with annealing it can be tough to do, and sometimes impossible with normal expander ball full length sizing dies. That expander ball pulling through can wreak havoc on your headspace consistency, as well as neck concentricity. A lot of people go to bushing sizer dies for this reason. I do a 2 step body sizing, then neck sizing process.

That's a lot of info to throw at you. If you don't anneal, and use a normal expander ball full length sizing die, my advice is to check your measurement, but you are probably fine. I've never seen a .010" bump from setting a die by instructions as has been said. Even cheap Lee dies if screwed all the way to the shell holder only bump the shoulder .004"-.006" on every caliber I've tried it on. That's how I used to load all my ammo. It isn't ideal, but it isn't that bad either.
 
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Godsdog

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If you have a borescope, or access to one, look at the same location on the inside of the case. If it’s too hot of a load then there should be something there. If not then check the bore for burrs or something?
Surprised it would be a pressure issue with no other signs of pressure though.
I definitely wouldn’t use that brass again till you figure it out though.
Pdog, I've reloaded since 1959 and I finally got a Bore Scope a coupla years ago, but I never ever thought of using it to check my brass for Incipient Head Separation! Thanks! A guy could check a whole "Lot" of one load where before, I'd cut a case in half to check the Incipient Head Separation. Most reloaders won't realize that Incipient Head Separation actually starts with your first firing to one degree or another. Most manufactured rifle cases made today are not made to the SAMMI Specs you see on the Case Diagram in the books. We see a ring on our newly fired case and think the Rifle has an oversized chamber when actually the darned cases are a coupla thousands or more undersized in the Web Area from the git-go!
 
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