Get these at the hardware store, they fly straight and work great.
(http://i718.photobucket.com/albums/ww190/ramtruck22/90713a16.jpg)You will need a pack of crown bolts t nuts 1/4 20.
(http://i718.photobucket.com/albums/ww190/ramtruck22/19dd040c.jpg)The middle will have to be drilled out some so your field point can thread. Use a 5/16 bit, drill it out til its about 1/8 deep so your point grabs a few threads.
(http://i718.photobucket.com/albums/ww190/ramtruck22/a031ebf6.jpg)Go have fun testing them out on some critters.
Great idea
Real great idea. Im on my way to the hard ware store now.