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deltaenterprizes
02-11-2024, 11:31 PM
I have been loading 9mm Luger almost 40 years a never had a case head separation while resizing the case!
It was not a big problem but I only had 2 more cases to load.
I measured the ID and it was a little smaller than 5/16 so I put the die in the lathe and used a 5/16 tap and with the tap still in there I used a small punch through the hole where the decapping rod goes and with little effort pushed the tap and broken case out of the die.

jsizemore
02-12-2024, 12:25 AM
Had a friend that had a case head separation in his 22 hornet contender during a match. He had a tap he used to remove the case body that was still in the chamber. He carried the tap in his range kit so I assume it wasn't his first go round. He alibied his last couple shots and continued in the match.

SoonerEd
02-12-2024, 12:58 AM
I have been loading 9mm Luger almost 40 years a never had a case head separation while resizing the case!
It was not a big problem but I only had 2 more cases to load.
I measured the ID and it was a little smaller than 5/16 so I put the die in the lathe and used a 5/16 tap and with the tap still in there I used a small punch through the hole where the decapping rod goes and with little effort pushed the tap and broken case out of the die.

Never seen that in a 9mm.

1eyedjack
02-12-2024, 08:23 AM
Had a separation next round wouldn't chamber! Front half of case stayed in chamber found rim on the ground. Found Front half of a jacketed bullet between firing line and target another time at our private range. Some weird stuff happens when we roll our own!

Rapier
02-12-2024, 09:39 AM
Used to see a good many of the case head separations on our range on a military base Rod and Gun Club range. The military makes no effort to seperate pistol fired brass from submachinegun fired brass, It all can be resized, but sub gun brass may have a ring inside the case at the web. Pluse the 9mm work hardens every time it is reloaded. At a point the brass just comes apart.
With a fairly clean, smooth chamber, a 10mm or 44 bronze brush, pushed past the case mouth, will pull the case, you really do not need a tap and the bronze brush will not damage the chamber.

country gent
02-12-2024, 10:28 AM
I have pulled separated cases with a bronze cleaning brush sometimes you need to go a size larger If I can get at it from the back I just push it in the case and pull it out. reversing the brush wedges the bristles giving it a good grip. Its not just the cases that cause problems but sometimes the guns. Bulges being sized back down over work the cases stretching and thinning it. Semi Autos more violent extraction is harder on brass. This is more so on rifles.

contender1
02-12-2024, 12:22 PM
If you were using "range pick-up" brass,, you MIGHT have gotten a piece of brass from a USPSA competitor who runs an "Open" gun in .9mm. They load the stuff pretty hot.

Glad you didn't have any trouble removing the broken case.

atfsux
02-12-2024, 12:34 PM
9mm cases in particular get the most abuse from being fired in open-bolt submachineguns. The chamber dimensions tend to be "generously over-sized" to begin with, with the chamber mouths often being rather rounded and slightly belled. Add to that, the case begins attempting to blow itself backward against the unlocked bolt immediately and can actually begin to travel outward and unsupported while still under pressure before the bullet has left the muzzle. Thing get even worse when a suppressor is attached, prolonging the backpressure within the case.

In extreme cases, you can sometimes find examples of ejected cases at the range that look like this.
323353

That photo demonstrates the location on the case where brass fired out of a SMG can experience stress. And it doesn't have to be an extreme example like that to work-weaken the brass. The deformation might be only slightly more to the naked eye than "regular" fired cases. But if an SMG shooter continuously reclaims his brass and keeps reloading and firing it,...you could easily see how that brass would begin over several loadings to start to thin or weaken. I've had several case head separations when firing my STEN, likely from exactly the phenomenon I've just described. As a result, I try to keep track of how many times I've reloaded my 9mm brass, and limit my use of them to just 5 reloadings. After that, I scrap them and start with a new batch.

charlie b
02-13-2024, 01:33 AM
I've had some issues with 9mm in my HK. They use the 'step' chamber so there is a ring on the fired case. The are harder to size than any other pistol case I've used.