I got this idea from a friend, and I used the basic body from his idea and modified the mechanism myself. It shoots a wooden barbecue skewer five to ten feet. When you make it, please send me a picture. I used a recycled plank that was a bleacher from a high school gym.
Step 1: Parts
Here are the parts/things you need.
-chop saw (or hand tools)
-coping saw (hand tool)
-cable staples (those thinges that are like staples that go on cable
-long bolt with nut on the end
Step 2: The Stock, and the guide
I suggest that you use a 2x4 piece of wood for the stock. There really isn't much to tell you except that you should know, all you have to do is to trace the shape of the stock on the piece of wood as well as making a V notch, and cut it out with a jigsaw. Mine is a 17" piece of wood and I put the center of the notch at the 9" mark from the front of the stock.
To make the guide I used 3 cable staples centered in the middle of the stock 1", 2", and 5" mark from the front of the stock.
This is mine: