Brass Problem

Dmay

Dmay

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This is two sides of the same piece of brass. What's causing the ridge? It is prominent enough to be felt with a fingernail, but only present on one side.

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The story:
Once-fired brass. 7x57R. Were resized and loaded. Some wouldn't chamber so I assumed the shoulders needed bumping. Pulled a few, tightened the die down to almost touching shellholder and resized. Still won't chamber. That is when I finally got looking closely and saw this. Looking at the loaded ones which won't chamber, it is evident on all.
It's not head separation, can't feel anything inside the case. Die can't be crooked, RCBS die in Co-Ax press. Chamber in rifle looks OK.
 

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Purely wild guess - were they previously fired in a belted chambering? No experience with a 7x57R, but I used 7x57 for years in a Ruger #1 - resized / reloaded hundreds of rounds - I never seen what your pictures show ... Or perhaps you have excessive case head protrusion out rear of chamber? Again, not really likely on a rimmed case, but typically brass is not going to expand to be larger or different shape than the chamber it was fired in - maybe caused by significantly excess chamber length from rim to case shoulder - but still not going to be bigger than the chamber was?

I notice in your second picture - sure looks like a "false shoulder" on that neck - are you making brass cases for your rifle from something else?
 
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Something is not concentric to the bore. Your chamber may be out of round. Try your fired brass in the chamber, then rotate it 180 degrees and try again, and finally rotate 90 degrees again in case you were initially in line with an oval chamber.
Can you measure your fired brass with a mic at the web to see if it’s round?
 
I'm thinking the 7x57R that these cases were originally fired in has a pretty generous chamber.

The cartridge "lays" on the bottom of the chamber, and when fired expands upward to fill the
void in the chamber, making the offset expansion at the web that you see.

You probably have a tighter chamber on your 7x57R, so you will have to size those cases more to
allow them to chamber in your rifle. Screw that die in to "bump over" slightly, and then size one
of those cases. You may find it chambers then. Dave.
 
I should have mentioned: The brass was virgin when I got it. Only fired in this rifle.
I hate to think the chamber is faulty....it's a $13,000.00 rifle!! Haha.....Blaser K95 Stutzen Attache...
 
Sounds like your chamber is slightly oval. Try orienting the case in different positions; I'd start with the bright ring to the bottom.

Also, looking at your 2nd photo, it looks like the neck isn't fully resized.
 
9.3mauser said:
Sounds like your chamber is slightly oval. Try orienting the case in different positions; I'd start with the bright ring to the bottom.

Also, looking at your 2nd photo, it looks like the neck isn't fully resized.
Click to expand...

Refer to post #4 and again, it looks like out of round. I would be torqued if my $13k rifle was like that. In the “gunsmith kinks” books they mention not to put a barrel in a vice clamped over the chamber area to cut a chamber as it will be elliptical when removed from the vice. Hope that you get this solved to your satisfaction.
 
Dmay said:
I should have mentioned: The brass was virgin when I got it. Only fired in this rifle.
I hate to think the chamber is faulty....it's a $13,000.00 rifle!! Haha.....Blaser K95 Stutzen Attache...
Click to expand...

AHHHHH! That puts an entirely different light on the matter. Out of round chamber most likely. :(
 
An out of round chamber from a quality manufacturer is going to be extremely rare. I managed to screw up some cases just like yours and it was a misaligned die and shellholder just like 250 Sav mentions.

This is still possible to do in a Co-ax if the shell plates are not grabbing the case equally and or the die is not floating laterally enough. Not being lubed enough can cause drag to one side.

I suggest looking at the die and resizing process first. Grab a buddies single stage press, put your die in and screw it down all the way to the shell holder and resize another bunch of 1 fired cases.

Next is this die for 7 x 57 or a specific 7 x 57R die? There's a few dimensional differences in the shoulder location of rimmed versus non -rimmed

Whenever brass doesn't fit I always assume the problem is my sizing process first before I look for other factors.

Like someone else mentioned, what's up with the necks?
 
Heddok said:
An out of round chamber from a quality manufacturer is going to be extremely rare. I managed to screw up some cases just like yours and it was a misaligned die and shellholder just like 250 Sav mentions.

This is still possible to do in a Co-ax if the shell plates are not grabbing the case equally and or the die is not floating laterally enough. Not being lubed enough can cause drag to one side.

I suggest looking at the die and resizing process first. Grab a buddies single stage press, put your die in and screw it down all the way to the shell holder and resize another bunch of 1 fired cases.

Next is this die for 7 x 57 or a specific 7 x 57R die? There's a few dimensional differences in the shoulder location of rimmed versus non -rimmed

Whenever brass doesn't fit I always assume the problem is my sizing process first before I look for other factors.

Like someone else mentioned, what's up with the necks?
Click to expand...

This still isn’t going to explain the out of round by .002” on once fired brass.
 
Re-looking at the OP's first picture - I made assumption that the solid case head was larger diameter than the case body - might not be so? Maybe OP could clarify for me - is the lip that you can feel with finger nail - is case body larger, or is case head larger? Work from idea that a brass case walls are going to expand very tightly to match the chamber it was fired in, then should relax a thousandth or so to allow you to extract it. The solid case head not going to change size much, at sane pressures. Does not really matter what configuration that it started from - can see pictures on Internet of 7.62 NATO (308 Win) that have been fired in 30-06 chamber, etc., or 303 British fired in oversize and elongated WWI chambers - the brass is only tiny smidgeon smaller than the chamber that it was fired in - otherwise a pretty exact copy of it.
 
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First - thanks to all for trying to help, I appreciate it a great deal.

Clarification:
The ridge is indeed downward....as in: brass is thicker toward the rim.
The dies are RCBS 7x57 Rimmed dies, not regular 7x57.

I have determined this is happening during resizing, not in the chamber. I measured a loaded round, fired it and the dimension just ahead of the rim did not change at all. And the ring didn't appear.
I moved the die into an RCBS press instead and used shellholder. Tightened die right down and resized. The ring still appears, but not as prominant, and all the way round the case, not just one side. The brass will chamber.
I am surmising maybe this die is very tight around the bottom. Perhaps I should back the die out a little instead of tightening it....that will be next....
 
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