Picked up a Shield 45 a few weeks back. First two times out, it ran without a problem. The next time out, I had four FTF's. For whatever reason, the slide didn't pick up the next round. The slide locked back as if the mag was empty. I sling-shotted the slide, and everything was fine. Went out yesterday and had one FTF, same as before. I'm using Federal 230gn FMJ. Anyone else out there having this issue with the new 45?