Had some interesting jams at Ben Avery today with my PM9 that I've never experienced before. Basically a failure to feed. Upon firing, the spent case ejected properly, the gun cycled, and the new rounds got caught on the way into the chamber leaving the slide about 80% of the way back to full battery. A very strong racking of the slide (almost needed a hammer) was required to get the unfired round out of the chamber.
Kind of similar to this previous thread, except the OP mentioned scratches on the case of the unfired round. In my case, the rounds were badly crimped at one single point on the case mouth and almost looked a little bent (pics below).
These jams occurred while using TulAmmo Brass Maxx from Walmart. I had 3 instances of this in the 100 round can that went through the pistol. My PM9 has about 500 rounds through it with no prior issues and is always cared for after firing. Mechanically speaking, the only possibilities that come to mind are polishing the feed ramp or perhaps replacing the recoil spring assembly, but both of those appear to be in good working order. I'm fairly confident it is the ammo, but please let me know if you have any thoughts or similar experiences.