[Aaron Ng]

Is the motor driving the dart spinning, yet the dart isn't moving? or is it stalled.

my best guess is either:

1. You forgot a bearing on the inside of the dart, and when the dart bottoms out, the brass fitting is being press fitted into the bearing hole.
2. The shaft collar on the end of your dart (the gearbox end) has shifted out, so that when you bottom out, the ACME rod unthreads itself from the brass.

of course, these are just guesses, and I cant really say more without more details or seeing it myself. If you cant fix it, your best bet would probably be to just move the mounting point on the shooter closer to the hinge, so you need less extension to get the same angle change, and just never bottom out the DART.

On a side note, we've also had many problems with our dart. The major one being that the magnet inside juts out too much, and disintegrated when we ran it, causing magnet dust to get all over the ACME rod. Taking these things apart is definitely not fun. =/