A rambling opinion.
I've heated frizzens to get more curve, hoping for more shearing action. I do this with the frizz red hot. I then anneal the frizzen by cooling slowly in a can of wood ashes. (Now is a good time to file off casting lines, file the frizzen surfaces smooth, engrave, etc.) Next I bring the frizzen to a red heat, and hold it there for ten minutes with an acetylene-rich flame, then dunk it in very warm oil. (This assumes YOUR frizzen is oil hardening?) Draw the temper to straw for the strike zone, and blue for the tail, pivot and cover.
The flint really oughta hit 1/2 way on the frizzen, or a little higher, if you can make that happen:
1) Try moving the flint out a little longer, or mount it bevel DOWN.
2) Last resort: your cock might be bent too far if it's hitting on the bottom 1/3 of the frizzen.