Brass inspection: potential case head sep?

[dwinters14]

I've been looking through the range pickup brass I have, and I know a good bunch of it has been reloaded. The bulk is Lake City 5.56 as well as other 5.56 that has had the crimps removed. Plus the range I go to only sells their reloads.

Now I resized about 100 of them, and so far 75% of them have that discolouration/ring right where the case separation would be. I stuck a paper clip in a couple of cases and didn't notice any groove or divet. I'm wondering if I'm just being paranoid, or if my resizing die is stressing the brass? I have a lee single stage with their full length resizing die. I set it up according to the manual and everything seems to be okay.

Can some more experienced reloaders tell me if I should toss this brass?

Thanks.

[ar15barrels]

so far 75% of them have that discolouration/ring right where the case separation would be.
I stuck a paper clip in a couple of cases and didn't notice any groove or divet.
I'm wondering if I'm just being paranoid, or if my resizing die is stressing the brass?
Can some more experienced reloaders tell me if I should toss this brass?

If there is no stretch groove inside, you are just seeing the expansion ring.
The expansion ring happens where the case wall thins out and is completely normal.





If you have a groove like below, that's a problem:

[dwinters14]

Okay that's what I thought, thank you. I'm just manually going through all the cases with a paper clip to feel for a groove. So far I haven't found a single 1.

[OpenSightsOnly]

Okay that's what I thought, thank you. I'm just manually going through all the cases with a paper clip to feel for a groove. So far I haven't found a single 1.

File the point of that paper clip so you have a bevel.

That beveled tip will catch the thinned-out section.

When in doubt, toss it.

[bazineta]

If you're going to be doing this a lot, one thing you might want to look at is one of the inexpensive 'Dr. Mom' otoscopes on Amazon; that'll allow you to easily examine the case interior. It makes incipient case head separation completely obvious and it's just ridiculously faster than using the paperclip technique.

I process a large amount of Lake City brass, and the 7.62 has nearly always been fired in machine guns, which can result in an incipient separation even on the first firing, so I wanted a faster way to find the problem, and seriously, this is fast.

[dwinters14]

File the point of that paper clip so you have a bevel.

That beveled tip will catch the thinned-out section.

When in doubt, toss it.

Yeah I made a mark on the paper clip (for when it's in the zone) and I would slowly and lightly drag it against the case and watch the wire to see if it would shift at all. Never did, not that it's a very scientific way of doing it.

If you're going to be doing this a lot, one thing you might want to look at is one of the inexpensive 'Dr. Mom' otoscopes on Amazon; that'll allow you to easily examine the case interior. It makes incipient case head separation completely obvious and it's just ridiculously faster than using the paperclip technique.

I process a large amount of Lake City brass, and the 7.62 has nearly always been fired in machine guns, which can result in an incipient separation even on the first firing, so I wanted a faster way to find the problem, and seriously, this is fast.

This sounds like a great idea, I'll look into one. I also have a bore cam I use on my car to check cylinders, so I'll give that a try as well and see.

[OpenSightsOnly]

I process a large amount of Lake City brass, and the 7.62 has nearly always been fired in machine guns, which can result in an incipient separation even on the first firing, so I wanted a faster way to find the problem, and seriously, this is fast.

IME, after FL sizing once-fired LC 7.62 brass, the thin white line shows up, not all the time, however, and if it does I just toss it.

Also, if a once-fired LC 7.62 brass has a bulge on one side of the case head, I don't brother processing.

[divingin]

Yeah I made a mark on the paper clip (for when it's in the zone) and I would slowly and lightly drag it against the case and watch the wire to see if it would shift at all.

I just run the straightened paper clip (with a short 90 degree bend at the tip) along the inside of the case wall. The thinning of the brass at the separation point is obvious - it causes the clip to snag a bit. No need to watch the wire.

[17+1]

If there is no stretch groove inside, you are just seeing the expansion ring.
The expansion ring happens where the case wall thins out and is completely normal.





If you have a groove like below, that's a problem:

I'll cut a few cases once the batch gets over 3 or so firings (semi auto brass) and inspect the inside of them for that groove. I'm using range pick up brass so I'm not too concerned about sacrificing it. Safety is more important.

I had a case head separation before during a silhouette match, was shooting my M1A. Was using ball powder, cold day, cold gun. Fired and shot went way low, the case and head were both extracted and case head flew straight up and hit me on the top of my head on the way down. Didn't damage the gun and we kept shooting. Rest of the ammo went off fine.

[dwinters14]

I just run the straightened paper clip (with a short 90 degree bend at the tip) along the inside of the case wall. The thinning of the brass at the separation point is obvious - it causes the clip to snag a bit. No need to watch the wire.

Okay then I'm on the right path, because I didn't notice anything.

Cutting a couple every so often seems like a good idea.

[TexasJackKin]

2nd or 3rd, to say it, yes cut a few open and have a look. even after you find one with the paper clip, cut it open to see what you felt.

[opos]

I bought a couple of dental picks (the kind the dental hygenist uses (with the sharp wire tip)...easy to use and the fine wire is great for looking for the bulge...also they work great for stubborn flash hole and primer pocket cleaning...I like them better than the paper clip and they are only a few bucks on e bay...nice little cleaning tools.

sort of like this one on e bay..

http://www.ebay.com/itm/1-Set-Dental-Pick-Mirror-Tool-Sculpture-Instrument-Oral-Tooth-Teeth-PR-163-/121521198400?epid=1044192331&hash=item1c4b3a5540:g:~koAAOSwi7RZG-rd

[Metal God]

The ring is quite obvious once you've seen the real thing but sometimes the sizing dies leaves a smudge around the same area that looks similar . The head separation ring is quite distinct and sharply defined compared to what the sizing die does .

Here is what you are looking for

[tonyjr]

If I see rings like above , they are scape .
To be honest , I find , more dented cases .
Most of time I find the plunk test finds them

[17+1]

Pic attached is of 5x fired norinco Chinese brass case cut open.

I haven't been running these reloads hard, so they should last a couple more firings. They do have a shiny ring on the outside after sizing but that's where the die is hitting, it's not actually thin.

Cut cases when I doubt, cheap brass FTW!