Built a prototype already. Ended up with 1:5-1 and Im not completely satisfied with power. Second unit I'm going to learn from my mistakes. Wanted you guys to check my metering math please. Going for 1:2-1 Chamber volume is 2297 ml 140.10 cu in Need 5.60 cu in of propane for 4.2% 40psi * x=14.7psi*5...

Sorry d hall. I meant volume on chamber not barrel.

I built my first spud cannon yesterday and I think I have found enough info on here to get me thru that project. What I really want to do is be able to convert what I have into a signal cannon. I have a chamber that is 3548ml. I tried masking tape at the barrel to chamber connection and the boom is ...