You should double your barrel length to 6' for a good ~1:1 ratio. You'll get a LOT more power/range out of it. Currently its somewhere around 2:1. If you make it that long though you'll need to reinforce it. If you can't find Sch80 2" pipe, you can potentially use Sch40 with duct tape support rings ...
Even when charged to 300psi, that tank won't last you long. What I do for my guns is attach a 20oz CO2 tank to a ~2 gallon expansion chamber (with a low pressure regulator in between, of course!) at 125 psi. Then use a second reg ($20 at Home Depot) at 80psi to the BBMG. Using some 3/4" PVC and stra...
Regardless, using hydrogen in a cannon is a very bad idea in my opinion. That H2 creation system would be messy and dangerous, too. It wouldn't have any real use for semi-automatic because you still have to exhaust the chamber and bring in oxygen. If you were to have that running the whole time, per...
Mr. Plow here. The hits just don't stop coming... First two of my closest friends die in May in a plane crash, and now one of the best online friends I've ever had passes away... If it wasn't for Chewy, I know I'd never be as fond of pneumatic cannons as I am. He helped me with more cannon-debugging...
Well, understanding pneumatic systems plus having the craftsmanship skills aquired in the process can be useful. For example, right now I'm working on assembling a Kegerator from scratch, the only components I need to buy being the tap and faucet.... Yippee!