Check this out:
http://www.foxnews.com/projects/pdf/Wal ... Cannon.pdf

Fox news:
http://www.foxnews.com/story/0,2933,335801,00.html

Video:
http://webshop.bcbin.eu/movies/WBC.SWF

The home age:
http://webshop.bcbin.eu/

I don’t know what the valve is, does anyone know?

Some constructive criticism: You need to take the sprinkler valve off and re mount it just after the last elbow, before the barrel. This way there is much less wasted air space that needs to be filled by each shot. Neat idea, good job, it reminds me of this: http://www.members.aol.com/markfh11q/full...

Hi there. I recognize that there is some interest out there in spring/piston systems, well because I got into Nerf a wile back I have some interesting links. I know that at least some of this stuff has been posted before. One NICE Fast Action Rifle: http://nerfhaven.com/homemade/boltsniper_far/ Bolt...

Make it a mortar that launches paintballs up into the air so that they fall back to earth, otherwise you may injure other players if shooting directly at them. Or you could use a water rocket: (Warning: lots of pictures) http://sciencetoymaker.org/waterRocket/buildWaterRocketLauncher.htm to launch t...