View Full Version : Case head separation
I had an interesting stoppage yesterday:
https://imgur.com/a/VmX9bXv
During a drill, I attempted to fire the third round in a triple tap. No hammer fall, no fire. I had not noted any unusual feel to the previous rounds. A quick glance at the ejection port showed a round partly in the chamber. Tap-rack attempted. As I retracted the bolt, I realized that the extractor did not grab the case. I dropped the mag and let the bolt go forward in an attempt to engage the extractor. Nope. I locked the bolt to the rear and placed the weapon on a table, pointed downrange. I noted that there was no firing pin indent, so this was a live round. I extracted the case with a knife point and saw that I had an unfired round stuck into another case. Both extracted easily, simultaneously. I saw that all bolt lugs were present, and there was no apparent damage, so I continued shooting. I found the case head later when I policed my brass. Ammo in question was 62gr 5.56 that I’ve shot a bunch of in the past without issue. Lake City brass.
Later experimenting showed that I might have been able to clear this more quickly by holding the charging handle back and whacking the butt on the ground. I was able to get the whole thing to fall out of the chamber on the second try. I don’t know for sure if it would have worked in a hot gun.
I’ll be checking headspace shortly, just to make sure.
I had an interesting stoppage yesterday:
Wow,
That's an interesting one for sure...
Seen quite a bit of that in certain remanufactured ammo and homeloads.
I had an interesting stoppage yesterday:
https://imgur.com/a/VmX9bXv
During a drill, I attempted to fire the third round in a triple tap. No hammer fall, no fire. I had not noted any unusual feel to the previous rounds. A quick glance at the ejection port showed a round partly in the chamber. Tap-rack attempted. As I retracted the bolt, I realized that the extractor did not grab the case. I dropped the mag and let the bolt go forward in an attempt to engage the extractor. Nope. I locked the bolt to the rear and placed the weapon on a table, pointed downrange. I noted that there was no firing pin indent, so this was a live round. I extracted the case with a knife point and saw that I had an unfired round stuck into another case. Both extracted easily, simultaneously. I saw that all bolt lugs were present, and there was no apparent damage, so I continued shooting. I found the case head later when I policed my brass. Ammo in question was 62gr 5.56 that I’ve shot a bunch of in the past without issue. Lake City brass.
Later experimenting showed that I might have been able to clear this more quickly by holding the charging handle back and whacking the butt on the ground. I was able to get the whole thing to fall out of the chamber on the second try. I don’t know for sure if it would have worked in a hot gun.
I’ll be checking headspace shortly, just to make sure.
Put up a picture of the case head/primer one the separated case. Was the ammo new or reloaded? Looks like overworked brass at first glance.
Seen quite a bit of that in certain remanufactured ammo and homeloads.
Yep. It's a risk you run on reman ammo. Especially if you load range pick up brass. I toss out/recycle brass that I can see has been loaded by someone else.
I've had about 4 or 5 of these separations out of 20 years of hand loading AR ammo.
Seen quite a bit of that in certain remanufactured ammo and homeloads.
Exact same thing happened to me during a class about six years ago. Fortunately the instructor knew what happened and used a broken case extractor to correct the problem in no time. I bought a Brownells Broken Shell Extractor shortly thereafter. So far, never had to use it. Ammo in question was Black Hills .223 55 gr. FMJ, Blue Box(remanufactured). Doo-Doo happens.
Put up a picture of the case head/primer one the separated case. Was the ammo new or reloaded? Looks like overworked brass at first glance.
I’ll have to add a good picture of the case head tomorrow. Brass was virgin Lake City, loaded by a smaller manufacturer with a good rep. I’ve shot perhaps 10,000 rounds of their stuff between pistols and rifles, and I like their products. I need to recheck headspace and consult with the ammo manufacturer before I can come to a conclusion.
RVTMaverick
02-21-19, 11:10
Hey 1168,
From what I can see in Your picture, to me it looks like just part of the "Rim" ripped off?
I don't see or actually, I am not understanding "Case head separation"..? LOL... I see it now, I was only getting the 1st picture for along while... I see it now.
FWIW: Years ago, I had a stuck round in the chamber that looked a lot like this, 1st, I removed mag., then, I closed the Butt Stock to the shortest position, next, while holding my carbine vertically, I banged the Butt Stock into the ground, at the sametime racking the Charging handle,... 2nd or 3rd hit, with the Butt Stock into the ground, I got the round out of battery.:cool:
I had an interesting stoppage yesterday:
https://imgur.com/a/VmX9bXv
During a drill, I attempted to fire the third round in a triple tap. No hammer fall, no fire. I had not noted any unusual feel to the previous rounds. A quick glance at the ejection port showed a round partly in the chamber. Tap-rack attempted. As I retracted the bolt, I realized that the extractor did not grab the case. I dropped the mag and let the bolt go forward in an attempt to engage the extractor. Nope. I locked the bolt to the rear and placed the weapon on a table, pointed downrange. I noted that there was no firing pin indent, so this was a live round. I extracted the case with a knife point and saw that I had an unfired round stuck into another case. Both extracted easily, simultaneously. I saw that all bolt lugs were present, and there was no apparent damage, so I continued shooting. I found the case head later when I policed my brass. Ammo in question was 62gr 5.56 that I’ve shot a bunch of in the past without issue. Lake City brass.
Later experimenting showed that I might have been able to clear this more quickly by holding the charging handle back and whacking the butt on the ground. I was able to get the whole thing to fall out of the chamber on the second try. I don’t know for sure if it would have worked in a hot gun.
I’ll be checking headspace shortly, just to make sure.
Hey 1168,
From what I can see in Your picture, to me it looks like just part of the "Rim" ripped off?
I see the second image has the classic case separation with the castle-like breakage line around the brass body. I really see no need to check head space on the gun unless this was a repeat problem.
You could easily drop some of their ammo into a case gauge to see if they're squeezing the brass down too much.
I need to take a couple pics of some case failures, etc. I certainly bet you won't be a magwell holder thereafter.
Case head separation comes from brass being resized too many times which stretches it out and therefore thins it at that spot and weakens it. Never heard of it happening to new brass especially quality headstamp like LC.
Does this manufacturer also load reman ammo? Perhaps they got some brass mixed up. Just don’t see how this could truly be virgin LC case.
SNIP Years ago, I had a stuck round in the chamber that looked a lot like this, 1st, I removed mag., then, I closed the Butt Stock to the shortest position, next, while holding my carbine vertically, I banged the Butt Stock into the ground, at the sametime racking the Charging handle,... 2nd or 3rd hit, with the Butt Stock into the ground, I got the round out of battery.:cool:
I couldn’t get the extractor over the rim to grab it for some reason. I think the way the cartridge was jammed in there, the head wasn’t centered enough to slip into the bolt’s recess.
I really see no need to check head space on the gun unless this was a repeat problem.
You could easily drop some of their ammo into a case gauge to see if they're squeezing the brass down too much.
Not a repeat problem. Good point about the case gauge. I’ll have to check if I have any more from this lot. I think I do. I’ll see about getting a case gauge.
I need to take a couple pics of some case failures, etc. I certainly bet you won't be a magwell holder thereafter.
Luckily, in this case, it wasn’t catastrophic and the rifle (and my hand, which was forward on the ~12” handguard) is unharmed as far as I can tell.
SNIP
Does this manufacturer also load reman ammo? Perhaps they got some brass mixed up. Just don’t see how this could truly be virgin LC case.
They do also load reman. This was labeled new. I generally buy their reman or seconds, but the new was on sale. I’ve given the offending case and the next round in the mag to the manufacturer, as well as a couple other empties from that lot, so they can evaluate them for their QC purposes. I imagine it is possible for a used case or reman round to get mixed in with new somehow. I’m not sure if that is what happened or not.
They do also load reman. This was labeled new. I generally buy their reman or seconds, but the new was on sale. I’ve given the offending case and the next round in the mag to the manufacturer, as well as a couple other empties from that lot, so they can evaluate them for their QC purposes. I imagine it is possible for a used case or reman round to get mixed in with new somehow. I’m not sure if that is what happened or not.
Probably the janitor found a case on the floor that fell out of the recycle bin and tossed it into the loading hopper or something. If handling used cases at all, they should be extremely careful to never let components from that run or rejects to have any chance of finding their way into the new run. Like sweep the floor, disassemble and clean tool heads and hoppers, remove all material bins and restock left overs, empty the trash and recycle. Only then bring in the new material.
I am sure they have a practice like that and some yahoo got lazy. Hopefully the box info can narrow it down to the day and shifts involved.
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