I haven't loaded with CCI primers for a good 20 years, but have not had any problems using Speer factory ammo that is loaded with them.

Last year I had a hard batch of Winchester primers, the brand I normally use, in .45 Colt. My Ruger Flattop was only setting off maybe 1 or 2 out of every 10 rounds.
I didn't suspect primers at first, but ended up trying a different hammer, heavier hammer spring, etc. Firing pin was hardly making a tiny mark on the primer. My 1892 lever gun shot the hard primers fine.
I opened a new pack of primers and loaded with them, every single one went off in the Ruger with a nice normal deep indentation.
I have since switched over to Federal primers for my pistol shooting.

Shooting Winchester 124 grain Nato FMJ out of my 5 inch MP9, I usually get one or two rounds out of each box that won't go off, when I look at the primer, there is the faintest dent in it. If you've changed out your striker, your firing pin isn't chipped on the tip, and your brass is the correct length ( not too short), I'd do as the others suggested and try a primer switch. Federal's are among the softest.

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