I have been shooting and reloading for 32 years....never ran into this. Perhaps you have? I was shooting my Ruger Security Six. All going well. Then I have one round no bang??? Keep barrel pointed down range for 30 sec. Nothing. Open cylinder, shows primer hit. OK. Reposition cylinder so that round would fire again. Once again, no bang. Keep pointed down range 30 sec. Nothing. First I thought, bad primer. They were Wolf primers. But I have shot thousands of them without any problems. Then I thought, I hope nothing is wrong with the firing pin or transfer bar. So I fired a few rounds from the same chamber in the cylinder that held the problem round. No problems. All went bang. Hmm. I pulled the bullet to see if there was anything visible that might explain it. What I found was bullet fine, powder fine. But at bottom of case, packed extremely tight against the primer were tiny rocks. It was not my corn cob media. They were a different color, size and texture. Is it possible that have these tiny stones packed tightly against the primer, prevented the primer from igniting? Or do we think it was just a bad primer?