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preacherJohn
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I'm still kinda hung-up on this case length thing, especially hand gun cases. Why would the length of the case matter if it chambers alright in the barrel?
Copper fouling
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FROGO207
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You set the length of the taper crimp for one length of brass and a different head stamp/brand/lot is a different length. The actual amount of taper crimp will be slightly different with each length. None of my 9MM's are tight chambered and I do not get your problem but one reloader I know has had these issues. He had fewer problems using more case mouth belling but I did not see why this worked but it seemed to. You might wan to try this or the sorting of brands of brass.
ETA: I get those same rings only in lead when I do not open the mouths up enough before seating bullets but the usually fall of when I put the bullets in a container or shortly thereafter.
ETA: I get those same rings only in lead when I do not open the mouths up enough before seating bullets but the usually fall of when I put the bullets in a container or shortly thereafter.
The case length is related to how much crimp is applied. That's why screwing the die in or out changes the amount of crimp, too... a crimp die converts vertical intrusion into the die into a horizontal crimping force. That's what a crimp die does. So if you have big variances in case length, you can get big variances in the amount of crimp.
Ordinarily, this doesn't have a lot of practical effect on most taper-crimped pistol cartridges, which is why few bother trimming their pistol brass. I think something else is going on.
Here's my hypothesis: It's the chamfering. You are thinning the brass so much that, in combination with a somewhat-long case, the horizontal crimping action is sufficient to actually or nearly shear through the brass. You are either cutting off the tallest bit of the brass (because you have thinned it by chamfering) during crimping, or you are setting it up to shear during firing. If it's not actually being fully sheared on the press, the combination of chamfering and crimping has gotten some brass to a degree of thin-ness that, under pressure in the chamber, the last little bit separates.
You don't need to chamfer pistol brass (especially "inside and outside" - why?). Pistol brass is crimped, and semi-autos, including 9mm, generally headspace on the rim. The rim is doing work at full thickness, and is also being worked in a way that rifle brass isn't. Don't thin that out... it's structural.
Ordinarily, this doesn't have a lot of practical effect on most taper-crimped pistol cartridges, which is why few bother trimming their pistol brass. I think something else is going on.
Here's my hypothesis: It's the chamfering. You are thinning the brass so much that, in combination with a somewhat-long case, the horizontal crimping action is sufficient to actually or nearly shear through the brass. You are either cutting off the tallest bit of the brass (because you have thinned it by chamfering) during crimping, or you are setting it up to shear during firing. If it's not actually being fully sheared on the press, the combination of chamfering and crimping has gotten some brass to a degree of thin-ness that, under pressure in the chamber, the last little bit separates.
You don't need to chamfer pistol brass (especially "inside and outside" - why?). Pistol brass is crimped, and semi-autos, including 9mm, generally headspace on the rim. The rim is doing work at full thickness, and is also being worked in a way that rifle brass isn't. Don't thin that out... it's structural.
I deburr/chamfer all revolver brass, but no auto brass. That said, just barely knock off the 90 degree edge, don't sharpen the case mouth.
If you got the brass ring from crimping, which is possible, you are way over crimping.
The only time I have had that happen was with revolver cases and a roll crimp on brand new brass with square case mouths.
If you got the brass ring from crimping, which is possible, you are way over crimping.
The only time I have had that happen was with revolver cases and a roll crimp on brand new brass with square case mouths.
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preacherJohn
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OK, that makes sense, I get it. Longer brass = more crimp. I had the taper crimp set pretty light, but what you're essentially saying is the longer case will increase the crimp. And this probably comes from those casings that I've never heard of from buying mixed brass. I didn't use to debur/chamfer my pistol cases, but I had a sticking issue with my PTX, so I wanted to knock off the sharp edges. I'll back the crimp off to nil, and widen the bell a little bit. I'll sort out the brass in lots and see if it affects anything. Thanks for the explanation(s). That ring still looks copper to me though.
Plated tends to buckle if the case has no/not enough flair, and jacketed is generally to tough to hurt with or without flair, but it could happen I guess, I just haven't seen it.
bullseye308
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TLDR what is the diameter of the ring? Is it bullet sized or brass sized? I’d start there to see if it is the brass or bullet.
Dudedog
Contributing Member
Not related to your issue but FYI
I can't tell for sure but it looks like that one piece of brass has the "step" about halfway down.
I had one separate at the step on me with a midrange load, leaving the front stuck in the chamber. Not a problem since it was practice but would would have been bad at a match or worse in a SD matter.
I send all the stepped stuff to the recycle can.
I can't tell for sure but it looks like that one piece of brass has the "step" about halfway down.
I had one separate at the step on me with a midrange load, leaving the front stuck in the chamber. Not a problem since it was practice but would would have been bad at a match or worse in a SD matter.
I send all the stepped stuff to the recycle can.
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preacherJohn
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Is this what you're referring to? That's just the way they come out of that PPQ's barrel. I would be throwing everything shot thru that gun in the recycle bin. And if that was the case, I'd might as well throw the gun in there too; there would be no brass left to reload.
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preacherJohn
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His eyes are better than mine, LOL.
higgite
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Look in the chamber of your PPQ 9mm and it will look very similar to this HK. That's why your fired cases are squeezed down at the mouth in your post #33.
Edit: Sorry for the large image. If a moderator or admin could reduce it, that would be great.
Edit: Sorry for the large image. If a moderator or admin could reduce it, that would be great.
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I see brass like that at the range sometimes, I pick it up as well, loads just fine.
No, he's talking about a specific type of brass that has a large, prominent internal step (which dramatically reduces powder space, and tends to cause case failures). Not something that is an artifact of being fired in a particular gun.
Dudedog
Contributing Member
You are correct guys, sorry I wasn't clear. It is an internal ledge in the brass that was made that way at the factory. I wasn't sure but there looked like there might have been one on the piece of brass (3rd pic post 18)
Maybe not but they are a pain.
Unless you are hurting for brass I would get rid of any of them you find.-> recycle can.
Maybe not but they are a pain.
Unless you are hurting for brass I would get rid of any of them you find.-> recycle can.
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I agree.
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preacherJohn
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I don't believe that is a "ledge or a step" in that casing. It looks more like a black crud and I don't know where it came from or how I missed it when I reloaded this bullet. I de-prime all cases then wet tumble them, so when I load them they are as shiney on the inside as on the out. I did see it as soon as I pulled that bullet. Something happened after the bullet was loaded. Maybe it was a tad wet, but most of my cases sit around a long time before they get reloaded because I have a habit of rotating them. Anything is possible, so....
Dudedog
Contributing Member
There would be no doubt it had it if you were looking at it. Wasn't sure from the pic but it just looked like it. One more thing to watch for when checking brass.
Anyway it's probably I good idea to watch for them in 9mm brass you pick up or get from some place else.
Anyway it's probably I good idea to watch for them in 9mm brass you pick up or get from some place else.
Jim Watson
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Man, people sure go to a lot of trouble for bulk pistol ammo.
I don't trim, I don't chamfer, I don't sort (except for chronograph and rest testing), I don't wash, I just dry tumble and Dillonize.
I recently found a little crescent of copper scraped up off the side of a plated bullet by an insufficiently flared case mouth. I increased the flare. A lot. If it enters the seating die, it has barely enough flare; I am not interested in "brass life" of mixed cases I will probably pop and drop at the next match.
One aggravating factor is that the powder die on my 550 will not stay screwed tight, it loosens and reduces the flare. I cut a cardboard washer and cinched down on the locknut which helped but did not cure. I am ready to look for a real 7/8" lock washer.
I have read about the HK bottleneck chamber. I wish I still had my Luger so I could look for the Official Original Bottleneck 9mm chamber.
I don't trim, I don't chamfer, I don't sort (except for chronograph and rest testing), I don't wash, I just dry tumble and Dillonize.
I recently found a little crescent of copper scraped up off the side of a plated bullet by an insufficiently flared case mouth. I increased the flare. A lot. If it enters the seating die, it has barely enough flare; I am not interested in "brass life" of mixed cases I will probably pop and drop at the next match.
One aggravating factor is that the powder die on my 550 will not stay screwed tight, it loosens and reduces the flare. I cut a cardboard washer and cinched down on the locknut which helped but did not cure. I am ready to look for a real 7/8" lock washer.
I have read about the HK bottleneck chamber. I wish I still had my Luger so I could look for the Official Original Bottleneck 9mm chamber.
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