[lurkingknight]

not specifically, I can't tell you exactly how it ended up like that, just that it did.

The compression jam was the problem that started the whole chain of events but I'm not entirely sure how the tappet skipped. With the gearbox opened I could see that the fin may have caught on a shim and twisted to get around the tappet post on the gear, I would guess that the sector was not shimmed enough leaving a larger gap on top of the tappet post that the tappet manage to slip itself into when I forced another cycle (or two... or three) after the compression jam.

Usually the first shot will fart with the jam, second if your gears are going fast enough will either strip your piston, or if you have steel teeth, bump/skip across the rack, or if you really force the issue, will catch mid cycle and jam the piston back all the way. Things tend to go the path of least resistance so there could have been enough of a gap to force its way in there.

That particular gun didn't have a sector clip on the tappet post, where a sector clip might widen that a tiny bit and prevent it from jamming under the tappet fin (in addiction to delay tappet going forward to help feed higher rate of fire) . My other 2 guns have sector clips while the one I had the problem on didn't

I reshimmed the sector a tiny bit tighter and higher and fixed the the jamming issue so it hasn't reoccurred. That's really all I got on it.