Ozark9mm,
You already have more rounds through your PT111 than I have through mine, and may never see the problem Joe, and other people have seen.
Seems the firing pin, springs, and striker, are all on one shaft inside the slide. The trigger bar engages a tang on the end of the striker shaft, and pulls it to the rear as the trigger is pulled. The trigger bar also has ears that ride in slots in the frame, and these slots curve downward. As the trigger bar moves rearward, the ears riding in the slots pull it downward, until it slips off the striker shaft tang, which lets the shaft (under spring tension) slam forward driving the forward end of the shaft (firing pin) into the primer.
The problem is that this long shaft is supported by a bushing, and to some extent by it's firing pin forward end, riding in the slide.
My theory is that the shaft is being pulled downward ever so slightly by the trigger bar moving rearward and downward, while pushing against the striker shaft tang. When the bar slides down, and then slips off the tang, the shaft rebounds upward slightly, and probably even oscillates, as it slams forward, putting undue stress and wear on the support bushing.
At least two people that I've corresponded with on the forums, have reported bushing fractures. I called Taurus, and they deny there is a problem, and told me they will not release drawings on the PT111, because they don't want owners disassembling further than slide removal. (I wanted to inspect the striker shaft bushing in mine for wear.)
I took the precaution of removing the metal plate on the bottom of my slide (careful, the spring under that plate is very tricky to get back in place), and applying gun grease liberally to the striker shaft, hoping some of it will keep the bushing well lubricated and prevent the problem.
So far, with about 500 rounds fired, it's still working!
Bill