[Hectic]

I choose #1 lol. Looks to me thats exactly what happened the last tooth (the metal one) broke for whatever reason (likely just cause it sucked) and the way it broke it is still in the piston but can wiggle and lay down almost flat when there is pressure put on from the front side thus allowing ylthe piston to slip forward one tooth. When it slips there is only one or two plastic teeth tryin to hold back the 400ish fps spring thus causing the teeth to fail just as the sector is finnishing its cycle so it was only enough sector to piston contact time to strip those few teeth as opposed to the whole piston.