I do wonder if the unusual shape of the Glock firing pin might contribute to the issue.
Some of the Federals I have are match primers, I think it's the magnums but I'm not positive.
I'll check later.
I'll have to run a test again and show what happens. IIRC, I was piercing like 1 of 4 or so at low levels and increasing to nearly all at mid-range loads, which is where I stopped.