[HumblePie]

Our design uses a toggle bolt "wing" attached to a guided cylinder to pull the bottom frisbee out. Toggle bolts are available at any home center, and include a torsion spring. In our case, we also riveted a small piece of lexan to the toggle to increase the reach through the shooter deck (YMMV).

The default position of the toggle is out in front of the bucket. When actuated, the cylinder is extended (rearward), and the toggle spring is compressed to allow the toggle to pass under the edge of the frisbee. The cylinder is then actuated in the pull direction, pulling the frisbee into the shooter wheel. As the frisbee passes over, the toggle spring will compress, allowing the frisbee to exit. The trick is to design you hopper so that the second frisbee doesn't have a chance to "shingle" and overlap the bottom frisbee, forcing the bottom frisbee to lift the second frisbee up in order to exit. That's when jams can happen.

Give it a try, it worked well for us.