When the first malfunction occurred, I knew immediately what had happened. The round was nosed radically up, with the nose of the bullet jammed almost vertically into the underside of the barrel hood. The breechface was jammed against the case wall, and the cartridge head was down in the mag. The rounds in the mag rattled loosely when the gun was shaken.
Dropping the mag and inverting it caused the top five rounds to just tumble loosely out, revealing the two rounds you see in the above photo.
Mag disassembled, looking at the bottom. See the two rounds wedged in there like that? One of them had enough friction with the side of the magazine that it bound up, and the spring and follower tried to force the bottom round past it, They were wedged tight enough that they needed to be poked out with some vigor.
The exact same thing happened to my M&P at Blogorado a couple years ago, using nasty TulAmmo in dirty mags in a dusty environment.
I don't know if there were any COAL issues with this batch of WWB, but regardless, I guess it's probably a good idea to clean my magazines every so often. These three have an average of 400 rounds through them since they have been cleaned.
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