wow! That is bad luck!
First, I would look at your fired cases. How do the firing pin marks look? Same as everybody elses you pick up at the range? If so, that basically rules out the gun.
Next, I would confirm the primers. I would load 10 in cases and try them. Sounds like you should get at least 1 which doesn't fire. If even 1 doesn't fire, I would call the primer maker and ask them to take them in return at their expense. Then of course try new primers.
If your primer strikes look shallow, then I would look at headspace issues and the firing pin.