I am useing the latest run of Jamison brass in my custom shop CZ 500 Jeffery. After fireing, the case has a semi sharp shoulder to it. Is this "normal" or is my chamber suspect. It does'nt look right to me, just want to get some feedback before I ship off the brass to CZ. Thanks

Post a photo. 'Semi sharp' is a subjective term.

George

First try with Pictures

You didn't enter the URL for a photo



The brass looks fine to me.

George

Looks good.

Mine seems to have a bit of a sharper shoulder after firing but I think that is due to the chamber reamer used here in Aust.

Thanks for the help with the picture George. So that crease is nothing to worry about? I'll see what it looks like after the next fireing. its my first time with this cartridge, and rather be safe than sorry. I have had a couple of large capacity case seperations!

What crease ???


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Brass also "looks" long. I'd check it as long brass can cause pressure spikes.


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Looks like the chamber bottleneck is a tad more angular than the factory case. As long as it loads fine, no problem as I see it. Hey Don...is that being fired from a BOLT GUN ????????????

quote:

Originally posted by Biebs:
Looks like the chamber bottleneck is a tad more angular than the factory case. As long as it loads fine, no problem as I see it. Hey Don...is that being fired from a BOLT GUN ????????????

Isn't that because the unfired case is made to fit in chambers where as the
fired one has fire formed to the chamber ?


Look at any factory rounds (30.06 etc) out of the packet and then after firing.
Shoulders are always sharper.

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500n, I understand what your saying about the fireforming to the chamber, the picture does'nt really do it justice. If you run your nail down the case it catches at the shoulder, it looks like the shoulder of these cases are going to get overworked, If thats normal for a 500J im good to go, I personally have never seen that before and on a case that size wanted second opinons, thanks for the replies.

It looks like a fired case thats been resized
to me.

it was not resized, it was fired and picked up out of the grass.

quote:

Originally posted by doubledown:
500n, I understand what your saying about the fireforming to the chamber, the picture does'nt really do it justice. If you run your nail down the case it catches at the shoulder, it looks like the shoulder of these cases are going to get overworked, If thats normal for a 500J im good to go, I personally have never seen that before and on a case that size wanted second opinons, thanks for the replies.

Remember, the case has fire formed to YOUR chamber, not mine or anyone else's. Every chamber is different (as much as they try to keep them the same), that is why you have Go and No Go gauges, to make sure the chamber is within the 2 gauges.

Re " it looks like the shoulder of these cases are going to get overworked"

Not if you only neck re size.

I am assuming you know how to do it and test in a gradual process where you need to resize in stages to determine the point where you don't need to go any further but the case still chambers. Hopefully this is before you bump the shoulder back.

I hope that is clear.

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The fired case looks good to me...very excellent shape. Other posts have covered the most important aspects already,

BUT...

If you're concerned about you brass send 3 fired cases along with the sizer die to the die maker and have them fit the dies to the case, OR if you don't have dies, send 3 to a die maker and have them make you a set of custom dies.

Be sure to indicate you want the shoulder moved back 0.002" or so only, the neck about the same less than the present neck ID and the base moved 0.001" to 0.002", and I would use a bushing sizer die so I can pick the bullet neck grip I like. That way your brass will only get a modicum of sizing and still be good to go for DG.

For all intents and purposes I wouldn't use brass fired more than twice for DG, I like once fired brass because it FITS and anything over two times is asking for problems.

But for non-DG game I work up a load that gives me case longevity at near max ballistics, but stop at 10 reloads. Large capacity cases don't last as long as the smaller variety.

I have loads for all my large game rifles from 338 through 50 cal(including my 510 Makatak that is slightly smaller than to 500 Mbogo) that go 10 reloads without a sweat, eject without a whimper and are within 50-100 fs of the max loads.

Many times case separations are caused by over sizing the case...following the die makers setup instructions without any thought to just what is going on. Setting the shoulder back too far causes the case to overstretch each cycle AND can happen if the chamber is cut too long to begin with.

This caught me on my first belted magnum. I just ran the sizer down to contact the shell holder and went to shooting. I would get two or three firings and the cases would come apart.

One of my mentors took pity on me and started the learning process. He made me a guage so I could see just what was happening during sizing.

The particular belted mag had a chamber cut ~0.020" deeper than SAAMI and I was using Rem brass that measured 0.210" at the belt instead of 0.220" so I was getting, in effect, ~0.030" of headspace to the shoulder of the case. After that I started headspacing on the neck of ALL belted cases.

You might also try another brand of brass for comparisons.

Luck

looks fine... but may not match your dies..

want the 99cent solution?

Take the fired case, cover it with a marker (sharpie for example) and go through a resizing effort ... set die to shell holder, back off THREE turns, and then start screwing in to see where it impacts your neck and shoulder ... if it hits about 1/2 way through the neck, you might have a die issue

quote:

Originally posted by jeffeosso:
looks fine... but may not match your dies..

want the 99cent solution?

Take the fired case, cover it with a marker (sharpie for example) and go through a resizing effort ... set die to shell holder, back off THREE turns, and then start screwing in to see where it impacts your neck and shoulder ... if it hits about 1/2 way through the neck, you might have a die issue

Good one Jeffoso.

I should have thought of that as I use the same method.

My Jamison brass looks the same once I fire it in my Heym 500 Jeff.......no worries as far as I can tell.

Gary
DRSS
NRA Lifer
SCI
DSC

Thankyou for the replies, there is no shortage of knowledge on this site.