1 bad primer , in a few hundred (223) . 9mm never an issue.
If you run light springs in your guns, you may have to hit some twice with the 9mm. Never had one not fire on the second hit though. SA/DA for the win. .223 and .308 has always been great.
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Also, I find that yellow UMC stuff to be much dirtier and smokey and that costs a lot more.