9mm Case Head Separation

GeoDudeFlorida said:
There’s a quota for dad jokes!!?? 😳
I’m bummed 🙁

I think since you already planned on going back to using the standard die the next step is just to wait and see.
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Yeah. Already swapped the die on my press and am ordering the “M” plug for my PTX. I’m done for now.

Thanks for your help.

BTW—Progressive Insurance commercials re: how to avoid becoming your parents are highly offensive to me. But I laugh out loud anyway.
 
higgite said:
Okay, now that y’all have my attention about Redding dual carbide ring sizing die, I see Midway and Opticsplanet both have it listed as discontinued :( and I can’t find it on Redding’s website. Am I not looking in the right places or is it really kaput?
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It seems some of the things I've read online indicates they replaced them with the NxGEN series dies. I haven't been able to confirm this though, so chalk it up to internet rumors.

That being said, the two NxGEN pistol sizers I have are be far my favorites. It is almost like the cases are lubed when using those things. No wasp waist on my 9mm anymore, not that it ever caused any problems.
 
ReL Walkalong's pic post, and follow-on with re RCBS dies.
No re-sizing/discontinuity/stress related to OP's issue.

Suggest same....

9mm-147g-GA-Pop-Slvr-Pwr-Pstl.jpg
 
CQB45ACP said:
I showed a picture of and mentioned this yesterday in the “What have you done” thread but wanted to start it’s own thread because it’s been eating at me.

Anyway, as I’m decapping & sizing cases, I found the pictured case when it wouldn’t drop in the gauge. I don’t recall feeling anything out of the ordinary while sizing. I certainly didn’t notice anything when I shot it on Friday. Seems like, but for the gauge, I wouldn’t have found it until I was priming for another reloading.

I have many questions (mostly second guessing myself) such as what did I miss BEFORE I loaded this case? I’ve looked at many past threads on case head separation with the overwhelming number being about rifle, not handgun.

I used the pictured pick inside this and other cases without any indications of incipient separation. (First use on “incipient“ in a sentence in my life.)

Thoughts and comments welcome.

View attachment 1187042
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1. What gun are you firing it from?
2. Is your die set up correctly to size the full case?
 
MEHavey said:
Looking again at the initial photo . . .
[https://www.thehighroad.org/index.php?attachments/img_0006-jpeg.1187042/]
. . . that didn't look like an undersized sizing die issue/output, per se.

I did think the discussion had turned whether Redding or other-brand dies would alleviate the problem,
and suggest that RCBS-carbide appears to be a candidate if Redding not available.
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Yeah I know. Could feel my wallet emptying. The discussion did bounce around a lot. Thanks.
 
The title muddied up the beginning of the thread, since that’s not what it is.

It’s a tight sizer with the round entrance to the carbide ring possibly to sharp, sizing down to, or past, where the case wall meets the solid case head. It’s a sizer that is tight enough to size the smaller neck diameter enough which is to tight for that far down a tapered case.

The best answer is a long tapered carbide insert, or an old tapered steel sizer, or the Redding two ring sizer, if they still make them. My one ring Redding sizer will do the same thing. Some cases don’t show that, most show a tiny bit, and some look as bad as the one in this thread’s opening post. Depends on the make up of the case.
 
Walkalong said:
The title muddied up the beginning of the thread, since that’s not what it is.

It’s a tight sizer with the round entrance to the carbide ring possibly to sharp, sizing down to, or past, where the case wall meets the solid case head. It’s a sizer that is tight enough to size the smaller neck diameter enough which is to tight for that far down a tapered case.

The best answer is a long tapered carbide insert, or an old tapered steel sizer, or the Redding two ring sizer, if they still make them. My one ring Redding sizer will do the same thing. Some cases don’t show that, most show a tiny bit, and some look as bad as the one in this thread’s opening post. Depends on the make up of the case.
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Yep. A question mark in the title would’ve done it.

For the foreseeable future I’m just going back to my standard Lee die which worked just fine for a good five years until I outsmarted myself. Maybe I’ll buy a new Redding but maybe not.

But, that doesn’t mean as time passes and memories fade I won’t make this trip again.
 
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CQB45ACP said:
Guess I should say—

This is a well used Winchester case—at least a dozen reloadings.

Most of those would’ve been with an undersized sizing die.

No expanding, no flaring, no crimping.

All moderate load of 4.5gr Sport Pistol & 115gr RN shot out of same 1911.
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That's probably your answer...undersized die overworks over time, 9mm is especially prone because it's not a straightwall, it's got the hourglass taper....undersized die works the hardened base even more...that line is basically where the taper would start....the undersized die is working that exact spot, and since it's the "hard" portion of the brass...gonna show stress signs earlier. I'd call a dozen loadings good with your method...9mm is cheap enough that you can toss all that, buy a thousand pieces of new brass, and start all over again.

Remember, there is no such thing as a free lunch. Undersizing has it's merits...but you have to pay a price.
 
EricBu said:
That's probably your answer...undersized die overworks over time, 9mm is especially prone because it's not a straightwall, it's got the hourglass taper....undersized die works the hardened base even more...that line is basically where the taper would start....the undersized die is working that exact spot, and since it's the "hard" portion of the brass...gonna show stress signs earlier. I'd call a dozen loadings good with your method...9mm is cheap enough that you can toss all that, buy a thousand pieces of new brass, and start all over again.

Remember, there is no such thing as a free lunch. Undersizing has it's merits...but you have to pay a price.
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Indeed
 
MEHavey said:
Would you believe . . "Over-sizing" ?
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I know there is a terminology disconnect...my first reloading manual in the 80s referred to a smaller dimension sizing die as "undersizing", to refer to sizing brass to slightly under the standard sizing die, so that's permanently stuck in my mind, and I'll probably never change, lol...too old for that. Not that I've ever hear of anybody using an over sized die (well, except for brass forming, or other unique instances), but CH4D will certainly make one for you if you are willing to pay for it, and wait several months.
 
CQB45ACP said:
Yep. A question mark in the title would’ve done it.

For the foreseeable future I’m just going back to my standard Lee die which worked just fine for a good five years until I outsmarted myself. Maybe I’ll buy a new Redding but maybe not.

But, that doesn’t mean as time passes and memories fade I won’t make this trip again.
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Yup. Sometimes I remember what I forgot but typically I just forget that I forgot something.
 
GeoDudeFlorida said:
Yup. Sometimes I remember what I forgot but typically I just forget that I forgot something.
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Sounding a little like Donald Rumsfeld—Do you remember this or is it something you forgot you forgot?

“Reports that say that something hasn't happened are always interesting to me, because as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know.”
 
I ruined a couple of cases apparently by not getting them all the way in the shell plate and scraping up a sharp edge of brass on the (Lee "U") sizing die mouth. I will go in with a pick and clean out the undercuts just in case. I will also go back to the Dillon die for heavy coated bullets.
 
CQB45ACP said:
I showed a picture of and mentioned this yesterday in the “What have you done” thread but wanted to start it’s own thread because it’s been eating at me.

Anyway, as I’m decapping & sizing cases, I found the pictured case when it wouldn’t drop in the gauge. I don’t recall feeling anything out of the ordinary while sizing. I certainly didn’t notice anything when I shot it on Friday. Seems like, but for the gauge, I wouldn’t have found it until I was priming for another reloading.

I have many questions (mostly second guessing myself) such as what did I miss BEFORE I loaded this case? I’ve looked at many past threads on case head separation with the overwhelming number being about rifle, not handgun.

I used the pictured pick inside this and other cases without any indications of incipient separation. (First use on “incipient“ in a sentence in my life.)

Thoughts and comments welcome.

View attachment 1187042
Click to expand...
I came across a case mixed with 9mm with a good buldge near the head. It wad stamped SAR 20.
 
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