The arrow in this picture indicates the metal plug with the groove cut all the way around it. There's a notch in the trigger group safety plate that the plug fits into. Somehow the plug is over traveling by a micro mm to slide under the striker release sear that is directly to the right side of the arrow. you would think the notch in the plate would prevent it from over traveling but I have inspected both pieces and cannot determine how it is happening. I see no irregular wear that would allow it. Just food for thought. Any advice is appreciated, thanks