case separation

[rjtfroggy]

This ever happen to anyone else? While at the range shooting a 308 with a known load I had a case come apart at around .6" ahead of the head, the primer wasn't cratered or back out and when fired there did not appear to be anything amiss, the shot actually was dead on.Brass has about 12 firings and is federal gold match, head space right at .002 and no other rounds before were affected.
I can't post a picture because on frustration I tossed it down range thinking here I go again this gun is jinxed.
What do you all think just a weak case or maybe something else? Oh by the way this was the 11th round fired and the new barrel was already dead on putting shots side by side @100 going to 200 tomorrow.

[acemisser]

Not being an expert like some claim to be on here...I have had the same thing happen...After so many
loading the brass gets pretty thin in the web area,above the head..If you start seeing a shinny ring
around the case in this area,the brass is too thin..When you see this,take a paper clip and make a little
hook bend on it.Go in the case and sometimes you can feel the ring..If so junk it....
I hope this helps you some...Like I said I aint no expert...Good luck...Be safe

[Jeff518]

I resize/reload 25-35 cases to 219zipper. I had one of those separate, after who-knows-how-many firings (10 at least). It did not affect the accuracy of that shot, but ended the day with half the case still in the chamber.

Now I check all my spent cases with the paper clip feeler method. I have not found any others eroded enough to feel.

P.S.
Most of my reloads (all calibers) show that scrape/bright spot just above the head after one fiiring.

Another double check is brass flow. If you are trimming case length back to spec more than once, all that brass is coming from somewhere...time to retire the case.

[Blue Avenger]

Had some win .220 and .25-06 both do it after second firing. Bought them at the same time. So I quit Win if that is the way they let others make stuff for them.

[Nor Cal Mikie]

Ever happen to anyone else??? More than a "FEW" times!
Shoulder bumping and neck sizing helps to eleminate that problem. Full length resizing with the expander ball pulling the neck up will contribute to the problem.
The case gets longer as you resize, you trim to length and reload. Where did that extra length that you have to trim off come from? From the case body stretching!
The .308 isn't a lightweight! Lots of power there and the brass really gets worked. After 5 or 6 firings and full length resizing, my guess is the brass at the web area is starting to get pretty thin.
By shoulder bumping and sizing the neck, you keep your brass from growing any more than needed. As the brass starts getting snug in the chamber, you body or full length size till the bolt closes easy. Bumping the shoulder back .001 or .002 keeps the brass from growing more than needed.
(I've got BR brass with 25+ firings on it, still doesn't need trimming and it's still going strong)
And, a "Broken Case Extractor" for every caliber you shoot is something you should keep in your range bag!
Nothing worse than 1/2 a case stuck in the chamber to end you fun! Bent wires, oversize brushes, gouged chamber walls from trying to remove the broken case?
Get the proper tools and keep them with you every time you go shooting.
Try a broken case in a M1A. After it's damaged the next few rounds trying to reload, you'll figure out you've got the front half of a broken case stuck in the chamber.
The broken case extractor saves the day!!

[wbm]

308 is known for that....especially in M14/M1A platforms.

[helotaxi]

308 is known for that....especially in M14/M1A platforms.

Which is exactly why 7.62 NATO brass is noticeably thicker than commercial .308 brass.

[bigedp51]

Did someone say something about commercial .308 cases and case head seperations? :-)
(you might be over resizing your cases or need to fire form them on the first firing)

The cases below were full length resized after each firing with the die making hard contact with the shell holder. (camover)





I don't have case head separations because I check them after each firing. ;-)

[wbm]

Very interesting data. Looks like Remington Plated and Norma may be worth a few more dollars.

[Nor Cal Mikie]

If the press is set to "camover" and the barrel headspace is set to that length of resized case, there's less chance of case head seperation because you won't be working the brass as much. Neck size and shoulder bump as needed.
You probably wouldn't be able to shoot factory loaded ammo because of it's length but with the headspace set on the "snug" side.

[helotaxi]

Very interesting data. Looks like Remington Plated and Norma may be worth a few more dollars.

With what appears to be a sample size of 1 for each case, I wouldn't put a lot of weight on the results. Doing the same series of load and shoot with a batch of cases from each brand would be more reliable and might actually give results that were statistically significant. As it stands, while it's well presented, it's anecdotal not actual data.

[Blue Avenger]

how old is the test, who made the brass under that name at that time, what lot number. It illustrates a difference, but nothing I would call current!

[bigedp51]

I have been reloading for over 45 years and have never had a case head separation.

The case will normally stretch the most in the web area on the first firing.

Knowing your rifles headspace and only bumping the should back .001 to .002 helps prevent the case from stretching on each firing.

Proper fireforming on the first firing will extend case life greatly, many new cases are shorter in cartridge headspace than SAAMI manufacturing guidlines. I have measured new cases that were .010 shorter than minimum chamber headspace and have further to stretch depending on where your rifles headspace is actually at. Jamming your bullets into the rifling to hold the case against the bolt face with a fireforming load is just one method.