[Pat McCarthy]

Just recently, I rebuilt the accumulator of my air cannon so I could enjoy it. I originally built it for a physics class projectiles project and never gave the PVC cement enough time to cure before I pressurized the tank, thus, why I had to rebuild it.



Anyway, mine runs off of compressed air pumped into the accumulator by a standard bike pump. I test fired it for the first time since I rebuilt the tank last week, and I have to say I love the results! I've been using pine cones and redskin potatoes as ammo, and I've had a pine cone go about 150 feet!

I also built an electronic trigger for the sprinkler valve, but getting to 24 volts with batteries takes a lot of batteries (Two 9 volts and four AA's in series). I have been using just 18 volts to run it, but it doesn't open the valve fast enough, so I've just been using the manual pressure release instead, with great results. So I'll probably just scrap the electronics.



My air cannon makes a very odd sound when fired, that I think has something to do with the shape of the inside of the sprinkler valve I'm using. But in any case, it's very satisfying when accompanied by the kickback of a firing.

On a side note, does anybody know the Michigan laws for air cannons? I've been unable to find anything pertaining to them through Google searching.