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Bulged primers and brass safety
Kevin_L
Member Posts: 2,011 ✭✭✭✭
I’ve run across a curious problem.
In some cases, while resizing & depriming some 9mm, the spent primer isn’t being ejected. The common factor is that those primers seem to be bulged as if someone reloaded them with too much powder.
I could adjust my extractor pin to deal with the matter but if the brass has been subjected to excessive pressure, it could be compromised.
Any thoughts?
🇺🇲 "The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants." - Thomas Jefferson 🇺🇲
Comments
I've seen this with primers that are crimped in (usually with military brass). I some times have to ream the crimp to get a new primer to seat correctly (or use a swagger to properly size the primer hole).
Possible (1) The primer metal is soft, (2) The primer is a loose fit in the case. (3) The case flash hole is too large allowing excess gas to bear against the primer. Good luck.
If the brass LOOKS good, both outside and inside, and is not bulged excessively, it should be good. All you can do is load ten and try them. Excessive force to size them would be an indicator of too much expansion, i.e., high pressure.
Good info, guys. If I take the brass and stand it on end (primer down), there are some that wobble because the center of the primer pushed outward when fired. Looks like a bunch of overloaded 9mm that I picked up at the range.
I extended the depriming pin so it removes those primers but, would you trust that the brass itself is still in good shape?
🇺🇲 "The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants." - Thomas Jefferson 🇺🇲
Usually, but it isn't an absolute, straight walled cases like 9mm don't have the same stretching problems bottle necked cases do. Providing the primer pockets are o.k., I'd just inspect for cracks like I always do anyway and use them. But hey, I'm cheap! Bob
also 'bulged' primers usually don't come from an 'over load' but from excessive headspace
AND one reason for buldged primers is when the round is fired the case swells into the chamber and the primer gets pushed back towards the firing pin and sometimes the firing pin will penetrate/puncture the primer. Not all will be the same. If the case moves back when fired the primer may look normal because the case moved back against the face of the firing pin.
At least have the headspace checked before a primer punctures and splatters your face.
Eye protection is a good thing. (safety glasses)
Any chance that this is the infamous "Glock smile"? It can happen on any with unsupported chambers, but most known on Glocks.
Look for the Lee Bulge Buster die.