Last Thursday saw a return to the P250C in .380 for some more trigger time as I finish up a story on it. I had a box of the Armscor it had such difficulty with in Topeka, as well as a box of the Sig Sauer brand .380 FMJ.
The Armscor still had issues, in the form of about five or six failures to go into battery. The rim wasn't sliding up under the extractor claw and a slap on the magazine floorplate would cause the gun to finish going into battery. Sounds like a rim thickness issue, or a combination of rim thickness and COAL (cartridge overall length).
I switched to the upper A-zone and the Sig house brand .380 FMJ, and the gun ran like a top for the rest of the session.
That Armscor is the only ammo that's caused issues in the gun; it's eaten Prvi and Tula, S&B and Remington white box with equal aplomb. I'd say that points to the ammo and not the gun.
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