223 Case Separation Troubleshooting Question

  • Last Post 15 September 2020
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zhughes posted this 17 August 2020

Hi all,

So I was at the range today and had a 223 case separate right about in the middle of the case.

The reload data I am using from Accurate is for 2230:

55 grain HDY BT-FMJ
Start load 22.4
Start velocity 2,976
Max load 24.9
Max volocity 3,278
Max Pressure 54,466 
COL 2.200

The projectile I'm using is a 55 grain HP BT-FMJ - it's only a couple thousandths shorter than the regular FMJ BT I have on hand.

My load was 24 grains, COL was 2.206, and the projectile passed the chronograph at 3,028 fps.

I have a few questions based on the above information.

  • Since everything checked out on the round itself as far as being under max load and fps was under max, can I assume pressure should be under max as well, or is it possible that something about the case could have contributed to higher pressure (like the case neck being out of spec)?
  • Could it just be an old cartridge that wore out that I didn't catch on inspection? If so, given the load was under max, could that situation ever become dangerous to the shooter - as in destroy the gun and parts fly?
  • The primer was completely flat, but I don't know if that meant over pressure or if that would have happened as a result of the case slamming backward against the bolt face. So - can that only happen from over pressure or is it possible the primer can flatten just from hitting the bolt face from force of the separation, even when pressure is under max?
  • How the heck do you extract the other half of the case out of the chamber?

Here's a picture of it:



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Spindrift posted this 17 August 2020

I hope you came out unharmed yourself. A case head separation is very unpleasant! 

I’ll try to answer your questions:

- pressure is, with high probability, under max. Recorded velocity, load data, everything fits.

-a case head separation can become dangerous to the shooter, depending on gun design. It is probably not good for the gun, either

- The reason for the separation (and flat primer) is excessive head space. The shoulder on your brass is set back to far. I would stop using that brass. There are techniques to salvage brass with to much set-back, but I wouldn’t go that route with the ubiquitous .223 brass.


- sorry, no idea how to extract the remaining piece of brass. 

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Bud Hyett posted this 17 August 2020

The easiest way to extract a separated case half is is using CerroSafe chamber casting alloy. Clean the barrel with a new bore brush and you might get lucky where the brush will pull the case out.

If not, then the chamber cast alloy set in the case and allowed to cool will do the job. Tap the plug with a cleaning rod and gently back the case out. Be careful to follow all directions to keep the alloy out of the locking lugs. 

This video covers the procedure very well. Chamber Cast Procedure 

Farm boy from Illinois, living in the magical Pacific Northwest

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Duane Mellenbruch posted this 17 August 2020

Some have driven a slug through from the muzzle and find that as the bullet passes the throat the bullet upsets and will then push on the case mouth and it will be driven out with the slug.  Some will just run a tight patch from the muzzle and accomplish the same thing.  Good luck.

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RicinYakima posted this 17 August 2020

The quick try, not always successful, is to force a .270/7mm brass bore brush thru the neck until there are bristles in front of the neck. Put some penetrating oil, Kroil, Ed's Red, etc. and soak for a few minutes. Then with a steel cleaning rod from the front, tap the mess out.

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Larry Gibson posted this 17 August 2020


Classic case separation. 

What FL die?

Full length sizing in FL dies swages the brass in from the sides and the brass flows forward causing "case stretch" and makes trimming necessary.  Over sizing exacerbates and hastens the problem, especially with "small base" (SB) FL dies or "AR" FL dies.  Using a standard .223 RCBS X-die will prevent case stretch, make trimming unnecessary and prevent incipient case separation. 


Concealment is not cover.........

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billwnr posted this 17 August 2020

you might also see if a thread tap will reach up that far.  If it does take a couple turns in the remainder of the case and then run a cleaning rod down the muzzle.   Will tap it right out.

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zhughes posted this 18 August 2020

Thanks for your help Spindrift. That was my suspicion as well, I just wasn't sure if you could get that under pressure.

I did go back through and find I have (thankfully) unloaded brass I purchased from a vendor online already sized.

Time to go through it all now.

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BigMan54 posted this 18 August 2020

No Ruptured case extractor ?

I have ones for .223, .308, .30-06 & .303Brit.

My Dad said they were mandatory for autoloaders & SMLE's.

Although I did see someone extract a ruptured .30-06 case with a empty .30-30 case once. 

Long time Caster/Reloader, Getting back into it after almost 10yrs. Life Member NRA 40+yrs, Life S.A.S.S. #375. Does this mean a description of me as a fumble-fingered knuckle-draggin' baboon. I also drool in my sleep. I firmly believe that true happiness is a warm gun. Did I mention how much I HATE auto-correct on this blasted tablet.

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M3 Mitch posted this 18 August 2020

you might also see if a thread tap will reach up that far.  If it does take a couple turns in the remainder of the case and then run a cleaning rod down the muzzle.   Will tap it right out.


This will work, but, a guy needs to be careful to only get the tap into the brass, not cut through the brass and damage the chamber.  Mastering the obvious, but, some people on here don't have a ton of experience. 

Applying a little Kroil and letting it soak for several hours is a good first step.

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Millelacs posted this 22 August 2020

 I have not tried this method, only talked to others about it.  Use it at your own risk.

I picked up the "cartridge" on the left at a range, out of curiosity.  The fired cartridge casing on the right is for comparison.

The one on the left is the top part of a separated casing with a complete cartridge jammed into it.

I'm told that if you have a case separation on an AR, and the top half is stuck in the chamber, just pull the charging handle back to load another round into the chamber.  The force of the recoil spring will wedge the second cartridge tight enough into the remainder of the first that you can get the half of the first casing out.

I don't recall if you needed to use a cleaning rod down the barrel or if the extractor was enough to get the casing out.

Again, I have never used it.  Use it at your own risk.

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zhughes posted this 23 August 2020

Thanks Millelacs.

I made a dummy round (no primer/powder) and used that.

That trick indeed worked like a charm.

I had to do it a couple times but it did work.

The only thing to add to your suggestion is that on the second time when it worked, the bolt was stuck so I had to "mortar" my AR to get the round out.

If anyone in the future reads this and doesn't know what or how to mortar an AR, there are plenty of videos on YouTube that demonstrate how to do it.

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Millelacs posted this 24 August 2020




I'm glad it worked for you.


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mashburn posted this 01 September 2020


After reading these posts, I thought I would give a interesting event that happened to me. Years ago in my prairie dog murdering years my brother-in-law and I ordered 2,000 .223  military cases from Midway. They were advertised as once fired and de-primed. We cleaned them, sized them and trimmed them all to length. We loaded every single one. I always check the head space on my reloads and they were sized to a very tight head space. Here is what happened, about 30% of these cases separated on the first firing. The only thing that I could figure happened was all of these were fired in a open bolt fully auto rifle. Would that stretch the cases to a point of near separation? Can anyone give me a better possibility. They were easy to remove from the chamber. All I did was run a .22 rf bore snake from the muzzle and they came right out. Fortunately we had much more ammo with us. We wound up tearing them down and salvaged the components. If I remember right, I had some cases separate when I was full length sizing when I raised the press lever up to extract the sized case.


David a. Cogburn

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Squid Boy posted this 01 September 2020

This was a common problem in Vietnam and the quick cure, since a live round was already jammed in the gun was to take it and smash it down on the butt while pulling the charging handle back at the same time. The separated part came out with the round about 99% of the time. Cleaning was essential. Thanks, Squid

"Squid Pro Quo"

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shastaboat posted this 15 September 2020

I would use a .243 (6MM) nylon brush.

Because I said so!

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