I have probably loaded at least 10,000 factory 209 primers and never had a bad one until this last 100. I have had 5 primers that were struck by my mod 12 firing pin and they did not discharge! Tried several times and then gave them to another fellow shooter to see if it was my firing pin and nothing! Is this a rarity or should one expect this every now and then? We took several of them apart and everything else checked out. Has this happened to others?