Thanks. You have given me several ways to go. I cleaned and lubed the firearm, and then using some of the spent cartridges tried dry firing the pistol.
It did get stuck twice when I did this, and I located 2 cartridges that I think cause the problem. I then replaced all 6 cylinders with spent cartridges, and dry fired the weapon 25 times, no problem.
I then went to 6 new unfired cartridges, and carefully pulled and lowered the trigger 25 times..not problem.
So I feel that your diagnosis was correct..it was the primers, and I will need to know that this can happen again. I am not going to get rid of the reloads as I have 500 rounds of them.
Thanks again, and I hope that this is the end of it.