Zane's Advanced Combustion Spud Gun

I work with the 14 & 15 year olds in our Church's Boy Scouts program. They had heard rumors of some of the stuff I used to do in high school, and they wanted to experience some of the fun I had. Among the many "fun" and usually dangerous things I did was build Spud Guns (also known as Potato Cannons). I instructed them on how to build their own basic combustion cannons, and they had a blast (literally) doing it.

I also built one to get them excited. Mine is much more complicated compared to the basic combustion cannons that they built, but I wanted to create a more advanced combustion cannon than I have ever built in the past. So here it is. There are various pictures and even a video of me shooting it off at the end. Click on the pics to make them bigger. Enjoy.

The cannon was constructed of ABS SCH40 pipe. It has a metered propane injection system to accurately allow me to get just the right amount of propellant into the chamber.











I built a circuit that allows a fan to blow inside the chamber and circulate the fuel/air mixture. The ignition system consists of a electronic grill ignitor and a dual spark gap inside the chamber.













My brother Kaylon shooting the Spud Gun from the hip.

Here is a video of me firing the cannon. Its a bit small and hard to track the spud flying through the air, but were estimate my cannon was firing the potatoes 300-400 yards.