Case head separation?

[BoomFlop]

So I'm a new Reloader.

These are 1x fired Starline 223 Rem brass.

Case prep was trimmed just to clean up brass ends, ran Sinclair mandrel with Redding dry neck lube, charged and seated bullet. I did not size them at all.

Can't be case head separation can it?

Thoughts?
Steve

 

[can1010]

looks like the brass expanded to fill the chamber which is normal. measure right above extractor groove and at the shadow line and you will see the difference. that area right above the extractor groove is real tough so it wont expand there giving you the shadow line your seeing but if that area expands then your primers will be loose or fall out

 

[milo-2]

I think the line is the back end of your chamber. A bent paper clip will reveal more if you can rig one up.

 

[BoomFlop]

I don't think it would be case head separation on first firing.

So you all are saying it's just normal to expand to chamber? I tried rubbing a paper clip, and don't think I felt anything but powder residue, but I'll research the paper clip method some more.

Thanks,
Steve

 

[Tiny Tim]

Put a short hook on the end of a paperclip and drag it across the inside of the case at the area of the ring. Looking for a valley in that area which would be a groove formed by the thinning brass. Have you measured the cases to the shoulder datum and compared to an unfired case? Ever have this issue with any other brass or ammo? In my experience, an incipient case head separation is indicated by a bright ring rather than a dark one. I think your good to go but you can check these things first. They are non-destructive. Worst case, you could sacrifice one and cut it open to examine it.

 

[sedancowboy]

This is where the cheap bore cams come in handy. But no case separation here just the brass expanding to fit chamber no worries! Load on.

 

[jimbires]

I agree with the other guys , you're fine . you are looking at the right place for a separation .
here are a few pics of cases that are separated , or ready to separate . they could help you in the future .

 

[BoomFlop]

Mine don't look anything like those ones. It is more just a difference between the rest of the case. I'll try paper clip. I'll also compare notes on unfired/fired and case head dimensions and report back. I write it all done in my notes.

Thanks
Steve

 

[BoomFlop]

Case head to "shoulder" average of 10 cases of new brass is 1.4560. The cases in "question" are 1.4565, 1.4565 and 1.4565. Cases that do not have the mark also measure 1.4565. Weird.

Web outside diameter of new (average of same 10 cases) was .3750. Web diameter of these are .3785.

That help?
Steve

 

[243winxb]

Head to shoulder (datum), new vs fired ok. New brass can get shorter or longer, depending on the PSI. Fired brass may give a false measurement, as brass has not fully expanded to the chamber on 1 firing.

.3785" ok also.

 

[243winxb]

My friend fires only factory ammo. I went thru the fired brass & this is the worst i found.

Its Federal 223. Fired in a large dirty chamber. The measurement are with in SAAMI specs. https://saami.org/
Different rifles did produce some fired brass where both measurement are the same. Some LC or Nato ammo. (Thicker?)

The start of a case separation may appear as a very thin shiny line. Near the case head or middle of the body. You do not have a problem there. Imo.

 

[243winxb]

In 1979 i started loading on a Dillon RL-450 progressive for an M16A1 carbine. No comparator or case gauge.
I set the fl die to contact the shell plate. Problem was the shell plate gave a different fl sizing at each station. Deck height difference.
The one station set the 223 shoulder back .014" causing case separations in the body. Lesson learned.

 

[P7M13]

Looking at your photo, I wouldn't worry. Know any reloaders near you?
Whats your tumble method?

here are a few pics of cases that are separated , or ready to separate . they could help you in the future .

Dang! 308 Win?
I've had 2 case head separations over thousands of rounds across all my calibers - my necks or primer flash holes usually give out first!

 

[19 Badger]

Your case will do the most growing on its first firing to fit your chamber. As long as your sizing die is set up correctly and only bumping your shoulder .002"-.003" shoulder separation will never be an issue.