OOB discharge due to casehead separation

[Slowmo]

I had an OOB discharge due to the casehead separating from the body of the case on the previous round fired, more or less leaving a brass sleeve in the chamber. Luckily it didn't seem to cause any apparent damage since the round was not able to generate much pressure before the unsupported case let go. In fact, the bullet from the OOB round barely even engraved in the rifling.

A couple questions:

What's the best way to get the brass sleeve out of the chamber? Tried a .45 caliber cleaning brush, and that didn't work. Currently have it soaking in Kroil and will try again, but wondering if there are any other tricks or if I should just buy a broken shell extractor.

What causes the casehead separation? I was shooting my reloads at the time, but I've reloaded and fired many thousands of rounds of pistol and revolver rounds and never had this happen. However, I'm comparatively new to reloading for open-bolt SMGs. Is this something peculiar to such platforms? I'm using a Pike barrel, and the fired brass does not come particularly swelled. Ironically, I had just cleaned the barrel and gun before this range trip.

Thanks.

 

[LGustin]

Remove the barrel and use a wood dowel going in from the muzzle end. Catch the edge of the case with the dowel and tap it out with a hammer. Worked for me.

 

[root]

The above works well.

Or a brass rod with a good flat sharp end.
Used that on a rifle when the wood just didn't do it.
Make sure it's brass or copper so you don't screw up the barrel.


I'm gonna guess old fatigued brass most likely cause.

 

[slimshady]

What brass were you using? Some brass these days has a step internally, thin where the bullet resides and thicker in the powder area. Famous for splitting at the step, even on the first firing of factory loaded ammo. IIRC, Maxxtech is the main provider.

 

[Slowmo]

What brass were you using? Some brass these days has a step internally, thin where the bullet resides and thicker in the powder area. Famous for splitting at the step, even on the first firing of factory loaded ammo. IIRC, Maxxtech is the main provider.

I'm not sure about the one that lost its head, I did not find it anywhere. I was shooting 147gr bullets that I do not think would have been capable of seating in one of the Maxxtech cases. I also try to keep an eye out for them to discard, but I have found them before, so anything is possible.

 

[mattnh]

Quite often you can grab it with a screwdriver or rat-tail file inserted from the chamber at a slight angle. Many times it doesn’t take much force to remove…. Other times, yeah beat it out from the muzzle…

 

[Slowmo]

Quite often you can grab it with a screwdriver or rat-tail file inserted from the chamber at a slight angle. Many times it doesn’t take much force to remove…. Other times, yeah beat it out from the muzzle…

Interesting idea. The only round file I have is too small, but a tap, drill bit, or large screw/Lag bolt might be able to grab it.

 

[Garrett]

Yeah. The stuff with an internal step is notorious for splitting, especially in an open bolt gun. Headstamps I’m aware of are IMT, FM, and one other - Ammoland maybe.

Because of this, I now inspect the inside of all of my cases prior to loading.

The one instance I had, the ring popped out pretty easily, just using a bore brush.

 

[strobro32]

Some of the makers of 9mm stepped brass.
FM
IMT
Ammoload
Maxxtech

I've wanted to invest in 9mm case remover. Using a rat tail file near a chamber makes me nervous. Rifle sounds ok but the front have of a separated 9mm case is too short. I would think scrapping the chamber would be too easy.

 

[Slowmo]

Yeah. The stuff with an internal step is notorious for splitting, especially in an open bolt gun. Headstamps I’m aware of are IMT, FM, and one other - Ammoland maybe.

Because of this, I now inspect the inside of all of my cases prior to loading.

The one instance I had, the ring popped out pretty easily, just using a bore brush.

Thanks for the other brass stamps to look out for, all I knew of was the MaxxTech. That picture is interesting. Is it just the angle, or is the primer on that separated case head unstruck? Your banana-peeled case is more or less what mine looked like as well. Did it cause any damage to your gun?

 

[Garrett]

That picture is interesting. Is it just the angle, or is the primer on that separated case head unstruck?

Yeah, the picture threw me at first as well. It does look like an unfired primer. It’s just a trick of the light. If you zoom in you can see the primer is missing, having blown out when the case failed.

No damage to the gun. It was pretty obvious when this happened, as I had been shooting suppressed. It went from really quiet to extra loud, as all of the gas and sound exited through the ejection port. The bullet did not exit the barrel.

 

[klyph12]

I think a 3/8 bolt will thread in a 9 mm case, turn it in by hand a till it grabs (you will feel it) - pull the case out. I had some Ammoload brass that separated 3 or 4 times a few years ago till I figured out the step in the brass was the problem and stopped using it.

Now I carry a 3/8 bolt in my range bag just in case (thankfully it has not happened again)

 

[Slowmo]

No damage to the gun. It was pretty obvious when this happened, as I had been shooting suppressed. It went from really quiet to extra loud, as all of the gas and sound exited through the ejection port. The bullet did not exit the barrel.

That is the same as my experience. Shooting suppressed and it was a loud, weird report out of the ejection port with some visible flash/sparks. The bullet barely engraved into the rifling.

 

[Slowmo]

I think a 3/8 bolt will thread in a 9 mm case, turn it in by hand a till it grabs (you will feel it) - pull the case out. I had some Ammoload brass that separated 3 or 4 times a few years ago till I figured out the step in the brass was the problem and stopped using it.

Now I carry a 3/8 bolt in my range bag just in case (thankfully it has not happened again)

I'll have to try that when I get home from work. I think I have some 3/8" bolts around the house somewhere.

 

[delta-10]

Slow mo that happened to me the first time I shot my new to me transferable Uzi SMG. Thankfully I had my work truck with me so I was able to dig something out of the truck and eventually get the case out of the chamber so that we could finish shooting for the day. That is the first and only time I've ever had that happen.

 

[slimshady]

Spare bbls can save the day...

 

[litfire145]

How did you try the .45 brush method? I just used that to remove an OOB case stuck in the chamber of a Sten. What worked for me was getting the brush lodged into the case and twisting my (junk) cleaning rod clockwise to twist the case free.

 

[Slowmo]

How did you try the .45 brush method? I just used that to remove an OOB case stuck in the chamber of a Sten. What worked for me was getting the brush lodged into the case and twisting my (junk) cleaning rod clockwise to twist the case free.

I just pushed it all the way through, but it crossed my mind to stick it in part way and then pull it back out hoping the bristles act like barbs. I ordered a 3/8” tap to try, but if no luck, I’ll revisit the brush. I tried a bolt but couldn’t really get it to grab.

 

[Slowmo]

Well tried a few more techniques with no luck:

1) stuck the .45 brush in and reversed part way hoping the bristles would be pinned back like barbs—> nothing
2) stuck a tapered flathead screwdriver in there until it grabbed, but twisting it just scratched up the inside of the brass sleeve without moving it
3) bent a fishhook and was able to grab the lip and try to pull it out, but the fishhook failed
4) took a .358 cast bullet and pounded it through muzzle to chamber hoping it would pull the sleeve out —> no luck

I’m not sure why it is so stuck in there, but I’m beginning to think that may be WHY the case head tore off (i.e. the body of the case got stuck, and with nothing to support the head, it blew off)

I’ve got a tap coming tomorrow, but not too optimistic that will work at this point. Looks like the melting point of brass is probably too high to melt it out without damaging the barrel heat treat (guessing a bit here). I suppose I could try to get some dry ice and freeze it loose?

 

[Samuel_Hoggson]

The reversed brush technique works best if you run the rod in from the muzzle, attach then lodge brush hard, then rap the rod hard at muzzle end. That's always worked for me. Trying to pull the rod back won't give same impact force.

Also, use a steel brush (not bronze).