Interesting. I have a Taurus PT 845...sweet gun but noticed that 2 of the 3 mags I have for it, I could only stack 11 rounds in them out of 12. Although I didn't have the firing issues you have had, it ended up being the spring mechanism inside the mag that was either backwards or the it was the floorplate that was turned around. A buddy of mine ended up troubleshooting it and fixing them for me. Long story short, it seems to me that Taurus mags are a bit cheap compared to others. If your problem isn't in the ejector area in the slide, maybe you'll want to tear down the mags and troubleshoot those. All my mags now fit 12 comfortably now...