I have a Lyman Power Case Trimmer and it has worked well for me. But, this time I'm having trouble with the cartridge getting stuck on the pilot. Sometimes very tightly stuck. I've tried sliding the case in and out before trimming and it seems fine. Then after trimming it gets stuck. I bought the expensive carbide bit that was supposed to eliminate that problem. I'm guessing that the bit is getting dull and smashing the case mouth vs trimming it. I've trimmed a few thousand cases so is it time to change the bit? Your experience will be helpful.