Step 4: Front Part

Now, Make the front. It is a 5in x 4in piece of wood. Cut it out and drill a hole for a dowl that is 1/4 of an inch deep on the upper front piece. After you drilled the hole, place some glue on the dowel and place it in the hole. To hold it in place better, rotate the dowel a few times.
No I haven't although I have thought about doing it. But the more you stretch the rubber band the farther it goes.(smaller the better but watch your fingers and eyes in case it snaps)
have you tried to measure it's fps? [feet per second]