Did it break when it opened or from being snapped shut? I always close them without an abrupt stop.
Bob Roller
I've given some additional thought to this matter. I was having trouble with this lock where I believed somewhere the lock was rubbing against the lock mortise. This was because when I set the lock off, the frizzen would appear to not open fully, and be "resting" against the flint.
Well, that was actually because the frizzen spring was too weak and the frizzen would fly open and then return so fast that it was not seen. I did a video with my phone, slowed it down to discover the frizzen did actually fully open before snapping back.
So, perhaps because of that (and I probably pulled the trigger 100 times when I was trying to find out the cause) I weakened the frizzen at the "L" point. And now with a stronger spring the force of flint impact put the "cu-de-gra" to the frizzen.