9mm case rupture

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Kezh1729

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I recently encountered some brass ruptures similar to the photos attached. Cases would be blown out from the rim, can someone help to identify the problems?
It only happens in brass with WIN headstamp, about 1 in 30 rounds, my reload data is relatively mild in terms of velocity(1080fps), 4.2gr Titegroup with Campro 124gr rn seated to about 1.100 OAL, nothing wrong with the powder thrower, brass have not been reloaded that many times and it only happens on some WIN headstamp brass.
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Hodgdon's website shows a max charge weight of 4.1gr of Titegroup for a 124gr bullet. If your bullet is seated quite deep, that could raise the pressure even more resulting in the case rupture. I've been reloading 9mm for over 30 years and have never had a case rupture and I have brass that has been loaded so many times you can no longer make out the headstamp.

Auggie D.
 
You are very close to Campro's maximum load of 4.3 grains. You are using an OAL shorter than Campro specs. I question if that is enough to blow out the case heads as shown. A borderline overcharge coupled with a case firing slightly out of battery may show such damage. You did check the reloaded cartridges for length in your barrel ?


http://www.campro.ca/index.php?id=1023&family=9 x 19&produit=Cal. 9mm 124gr RN FCP
 
According to Campro their recommended seating depth is 1.120, for that OAL it doesn't pass the plunk test for my Shadow 2 so I adjusted to 1.100.
 
It looks as if the case is expanding into the feed ramp area, and failing there.
I would suggest cutting back on your load, and if it only Win cases that are failing, don't use them.

You mention that the cases have been reloaded before. I suspect they are expanding into the ramp area, getting sized back, expanding again, and eventually failing.
 
What type of the Campro 124gn? How the primer looks like? I reloaded Campro 124gn RN at 4.4gr, AOL 1.14 through a 4.5" or 5'' barrel. It seems like the pressure is not high.
 
Titegroup is a wickedly fast powder.
It's even on the fast side of what's recommended for the 115 grain pills.
Power Pistol or N330 might be more up your alley.

Secondly, it really looks like the brass temper can be off on those WIN cases.
Did they spend a little too much time on top of the wood stove?
 
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