[lurkingknight]

pretty hard for that to happen, it's possible the plate is bending but I've never seen that behavior before due to a bending selector plate. Are you sure the cutoff lever is ok?

put the sector gear and the trigger in with or without the trigger spring... put the halves of the gearbox together.. pull the trigger all the way back so it pushes the sled forward... rotate the sector gear slowly through the cycle. The lever should lift the sled off the trigger and it should snap back. If it doesn't then replace the cutoff lever.

The cutoff lever can look fine but the lump that meets the cam on the sector gear can still wear down in height and not flip the sled high enough to lift it off the trigger.

The other issue it could be is that the contacts are holding the sled too tightly when it engages and it's taking several bumps for the cutoff to knock it loose.

If this is a new behavior then it's more than likely the cutoff, if it's always done it, it could be trigger contacts being too tight. It can also be both.

Slight chance there's a bit of overspin involved if it's always done it, but most guns overspin a little anyways, you just don't perceive it.