After 52 years, and 100K + rounds, I had my first misfire today. Brought the round home to diagnose what happened and found that the primer had evidently flashed just enough to have a burned look, but not enough to ignite the powder. There was no evidence of a piece of corn cob in the flash hole or any other occlusion. The primer had a strong firing pin dent and this action has been optimized for solid ignition. So it looks like a simple bad primer. I have shot nearly 2 bricks of this lot of CCI 450's and never experienced any problems. I guess if you drop the pin on enough of them, you will eventually find one that fails.