Honestly I think it's more common of shooters who have never shot the little guns. That small grip takes some getting used to. I have had two of the larger P9s with no issues and the first trip with the PM9 (which is the same size as the CM9 btw) I had 3 failures to lock back. The third time I actually felt my thumb riding the slide stop lever. After making a grip adjustment no more issues.
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