Case Head separation. Worst that can happen?

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Rule3

Rule3

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Case Head separation.

When this occurs what actually is the worst that can happen??

I realize it is is something that we don't want, and cautious reloaders check cases with a paper clip or dental tool, but when it actually splits in the camber how bad is that?

I have had it happen once in a AR 15 (556) It extracted the case head, the next round went in and stuck in the upper half of the case when I extracted that it pulled out the top section of the case. It was brass that had only been reloaded twice, Chalked it up to a bad piece of brass as no others have failed.

It is not something that we want to happen but what damage can or does it do to the chamber?

So can separation actually cause a Kboom or what?
 
In a Rem 760 pump, case head separation, nothing. In a 1903 Springfield, gas and particles will come back thru the bolt, mine was from a defective ruptured primer. Depends on the action type. Had separation (not head) in the body of 223/5.56 in M16 and 44 mag. in Marlin lever action. No damage.
 
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Say in a standard direct gas AR 15 and/or a Bolt action 223/556?

I am not downplaying what happens but is it really all that serious??

Perhaps the analogy of a 357 Mag brass splitting in the cylinder, Nothing really bad happens other than loss of pressure/velocity. The "explosion" or pressure is contained in the cylinder. Would not the same happen in the chamber of a rifle?
 
Generally speaking, nothing happens, except you will probably have the front part of the case stuck in the chamber.

They can usually be yanked out with a bronze bore brush.

There is no catastrophic gas release into the action because the case breaks further in the chamber where the thicker case web ends.

So what it left still properly seals the chamber.

It was so common 100 years ago the military issued broken case extractors so you could easily get it out and keep right on shooting.

rc
 
Worst case scenario?

Hot, high pressure gasses escape and ruin your day. The brass case is there to seal the rear of the chamber.

It wouldn't be nearly as bad as a rupture, and as rcmodel pointed out, it wasn't uncommon back in the day, but your taking an unnecessary risk if you do it frequently.

It will leak some gas, which isn't good. Have you seen a cratered bolt head from primers leaking?
 
Gas port - case head separation

Modern firearms may have a gas port or system to bleed off pressure if a case fails. The Remington 700 types have a bolt that is said to have 3 rings of steel, giving good protection. Some bolts may have a different type of extractor.
th_edit%20Rem_zpsmigtqqce.jpg
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Depends on the action design. A case head separation in the 1903 Springfield, the 1917 Enfield and the older model 70 rifles are sometimes spectacular events because of the coned breech.

i was present on a firing range when the gent at the next bench experienced a case head separation with his beautiful pre-WWII model 70 Winchester rifle. i'm a lefty and the guy was sitting close to me.

The floorplate, follower, spring and cartridges were blown from the rifle. The scope was bent and the stock was split. The receiver ring was cracked. The mans face was bleeding slightly and his glasses had been splattered with high pressure gas and brass fragments.
 
I've personally had a catastrophic failure that destroyed an FAL. It was likely a case head rupture, rather than a standard case head separation, but it blew the extractor claw through the side of the receiver and blew the front end completely off the rifle.

I was hit in the arm by the bolt carrier and rat tail as it was launched into low orbit, and my support hand was shredded a bit and peppered by steel fragments from where the barrel separated from the upper receiver.

Here's a thread from the FAL Files with a few photos of the destroyed receiver:

http://www.falfiles.com/forums/showthread.php?threadid=142685

The funny thing is that I didn't start the thread, but happened to stumble across it and recognize the photos of my receiver!

This is definitely a worst-case scenario, but I would consider this to be an anomaly, rather than the norm, when it comes to case failures.
 
Not directly related but similar results:

I had a primer punch on a .223 in my Ruger American last Friday. I was shooting some reloads and the particular load was no where near max.

It scared the crap out of me! Not use to seeing smoke in that area! Gun oil ran out of somewhere as well.

It was a CCI primer. I'm going back to Winchester primers for everything. Too many CCI issues for me lately.
 
I've personally had a catastrophic failure that destroyed an FAL. It was likely a case head rupture, rather than a standard case head separation, but it blew the extractor claw through the side of the receiver and blew the front end completely off the rifle.

I was hit in the arm by the bolt carrier and rat tail as it was launched into low orbit, and my support hand was shredded a bit and peppered by steel fragments from where the barrel separated from the upper receiver.

Here's a thread from the FAL Files with a few photos of the destroyed receiver:

http://www.falfiles.com/forums/showt...hreadid=142685

The funny thing is that I didn't start the thread, but happened to stumble across it and recognize the photos of my receiver!

This is definitely a worst-case scenario, but I would consider this to be an anomaly, rather than the norm, when it comes to case failures.
Click to expand...

I saw the pictures and followed up incidents of Chilean surplus ammunition. I have written extensively on old, deteriorated gunpowder, and what happened to you is consistent with a high pressure incident caused by old gunpowder.

All that surplus ammunition on the market came from military inventory. The owning military kept that stuff for as long as they could, but their trained Ammunition Technicians inspected that stuff and determined a couple of things: 1) the ammunition was no longer safe to store and 2) the ammunition was no longer safe to issue. The second part is probably why your gun blew up, old gunpowder has burn rate instability problems and pressures spike. The collective shooting community is in denial about this, but old gunpowder gets dangerous with age, and you found out one of the problems with old ammunition loaded with old gunpowder, it will blow up your gun.

These are threads which I provided information on old gunpowder and old ammunition.

Old Powder Caused Fire!
http://www.thehighroad.org/showthread.php?t=788841


Old powder

http://www.thehighroad.org/showthread.php?t=787843


Shelf life of reloads?

http://www.thehighroad.org/showthread.php?t=758305


Look at the pictures in this thread:


Has anyone else had Vihtavuori N140 corrode in loaded ammo?

http://www.falfiles.com/forums/showthread.php?p=3745264

The green corrosion inside the brass cases came from nitric acid gas outgassing from old deteriorated gunpowder. This nitric acid gas also attacks the brass causing case splits. When the corrosion is extreme it will cause pin hole through corrosion of the case. I have seen all of these.

Gunpowder lifetime is unpredictable, a rule of thumb is 20 years for double based, 45 years for single based. Some fails sooner. Hardly any gunpowder is safe past 45 years. Old gunpowder in bulk will autocombust. I would not trust your keg of old gunpowder, I would get it out of the house. Old gunpowder in cartridge cases will blow up your gun. Heat is the worst enemy of gunpowder. Temperatures over 86 F accelerate the deterioration.

Your rifle blew up because of extremely high pressure. Rifles are structures built to carry a load. While rifles are not aircraft, the basic structural load limit philosophy is similar:


http://adg.stanford.edu/aa241/structures/loads.html

The FAA establishes two kinds of load conditions:

•Limit Loads are the maximum loads expected in service. FAR Part 25 (and most other regulations) specifies that there be no permanent deformation of the structure at limit load.


•Ultimate loads are defined as the limit loads times a safety factor. In Part 25 the safety factor is specified as 1.5. For some research or military aircraft the safety factor is as low as 1.20, while composite sailplane manufacturers may use 1.75. The structure must be able to withstand the ultimate load for at least 3 seconds without failure.

That overpressure cartridge you fired exceeded by a huge margin, the ultimate load limit of your firearm. The consequence was a blown up rifle. This is not a fault of the rifle or its designer, your rifle would have functioned perfectly with ammunition at, or below the limit load.
 
Is a "case head rupture" the exact same thing as a "case head separation" ??

rupture sound more explosive or violent ??
 
Rupture is different than case head separation. With a separation the head is intact, just separated from the rest of the case.

attachment.php



A rupture is where the case head, or right by it, blows out. Don't have a pic handy.
 
i dont think much will happen maybe a bit of gas escape. no way will it blow up a gun.

i had a bunch of .223 brass, "once fired" that did it and i never had any problems.
 
I've had case head separation on .303 quite a few, 11.75 Danish many and one .223. Quite a few case failures on .38 spl,.44 mag and 9mm Israeli sub gun ammo (wow hot stuff). No real damage to the firearm.
 
Head Separation VS Rupture

Old military rifle with excess headspace or undersize ammo, head to datum.
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[/URL][/IMG] This is a rupture from bad brass.
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I've only had it happen once and it was in a NEF Handi Rifle. Nothing happened.
It was complete separation. Here is the result. When I broke it open it just spit the small piece out and I had to dig out the remaining.

The rifle had bad headspace issues. That case had only been reloaded twice when it did that.

002.jpg
 
From what I understand a case head separation occurs when you try to retract the fired round from the breech and the brass splits at the case-head leaving the rest of the brass in the chamber.

With that in mind, I've had 2 case-head separations in my Lee Enfield No4 Mk1. There was no difference when firing, I could only tell I had a case-head separation when I retracted the bolt. If you get a case-head separation failure from a factory load, for example, then the bolt should be able to withstand the pressure generated. I have a hard time believing that a catastrophic failure would occur due to a case-head separation. It looks like the discussion here is case-head separation/case rupturing due to dangerous over pressure loads.

I've shot some factory 8mm Mauser loads in my Yugo M48 where there wasn't full case obturation and a lot of smoke/gas would come back through the chamber, out of the bolt and into my face. Luckily it wasn't hot or painful (felt like someone coughing in your face, albeit a bit dusty) and there were no issues. I know that case obturation isn't the same as case-head separation but what is similar is the gas work back through the system towards the user.
 
From what I understand a case head separation occurs when you try to retract the fired round from the breech and the brass splits at the case-head leaving the rest of the brass in the chamber.
Click to expand...
The case head has already separated, or nearly so, upon firing, so that upon extraction the forward part of the case remains in the chamber.

The case head separated from too much stretching going on, whether because of excess mechanical headspace, or too much head clearance caused by improper sizing.

Explained more here:

http://www.thehighroad.org/showthread.php?t=734058
 
When the case head completely separates on firing, all the pressurized hot gas is turned loose inside the locked breech. There is no part of the case left that will seal off anything toward the breech bolt.
It is one of the most dangerous conditions you could imagine, right up there with a bore obstruction. All that hot gas has to go somewhere, and it will. Different guns will handle that, or fail to, in different ways.
Strong receiver and low pressure load? You might get away with it.
Very high pressure load in any action? Don't bet your eyes and hands on it.
One thing that never seems to come up in these discussions and should is that volume of super-heated gas under that much pressure has all the characteristics of an effective cutting torch.
 
BWB said:
When the case head completely separates on firing, all the pressurized hot gas is turned loose inside the locked breech. There is no part of the case left that will seal off anything toward the breech bolt.
It is one of the most dangerous conditions you could imagine, right up there with a bore obstruction. All that hot gas has to go somewhere, and it will. Different guns will handle that, or fail to, in different ways.
Strong receiver and low pressure load? You might get away with it.
Very high pressure load in any action? Don't bet your eyes and hands on it.
One thing that never seems to come up in these discussions and should is that volume of super-heated gas under that much pressure has all the characteristics of an effective cutting torch.
Click to expand...

:confused::confused:

"all the pressurized hot gas is turned loose inside the locked breech".

Seems a lot of it went forward with the bullet.

"right up there with a bore obstruction. "

Certainly seems like a separated case does not case the same effect (affect) as a bore obstruction

Pressure will escape to the point of least resistance so it's hard to say if the bullet moved forward before or at the same time as the case split.

I only had it occur once in a 556 and really could not tell it happened until the next round did not chamber.
 
Perhaps a more careful reading of my post would answer some of your questions - and assumptions.
 
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