Combustion Cannon with stand

[Haniball1337]

Hi everyone. I want show you my Potato gun, what I made. For me it is little ugly. I need to clean it but it works and it is fueled via 100 ml syringe btw sorry for my bad english. I fuel the gun from syringe using 100 ml of propane-butane and cannon never almost failed. Is it good ratio of fuel? In my calculation I need 115 ml but i am not sure about that.
Specifications:
- chamber volume: 3.5 l
- barrel diameter: 5cm
- barrel length: 1 meter
- range: about 80-90 m
- Piezo BBQ ignitor
- fuel: Propane-butane for lighters
- ammo: Potatoes, has someone knows good ammo for 5cm diameter barrel?
- removable barrels
Extras:
120 mm Fan (runs on two 9V batteries)
Wooden stand (95 cm high)
Funny story: I shot twice times with it and the fan started to move so I used super glue and baking soda method to repair it and by accident i hit one propeller with glue and now it is stuck. For now I don't know how to remove this glue.
Photos
https://imagizer.imageshack.com/img921/1261/yII5kr.jpg
https://imagizer.imageshack.com/img921/9837/2usDtQ.jpg
https://imagizer.imageshack.com/img921/6642/559KCd.jpg
https://imagizer.imageshack.com/img922/3804/B5Gr04.jpg
https://imagizer.imageshack.com/img921/7459/nZgsQ1.jpg
https://imagizer.imageshack.com/img923/7726/uLKW0H.jpg
https://imagizer.imageshack.com/img923/1374/rZeDGE.jpg
https://imagizer.imageshack.com/img924/1303/ivUM5N.jpg
https://imagizer.imageshack.com/img922/4994/Qx0kay.jpg
https://imagizer.imageshack.com/img924/7238/BxbQol.jpg

[jackssmirkingrevenge]

Nice example of a "traditional" combustion and good on you for using syringe fueling!

I would say the ideal quantity to inject if you 3.5L chamber volume is accurate would be 130mL, so you might be injecting a little under if it's a 50:50 propane:butane mix.

[Haniball1337]

Thanks. I don't see on bottle any words about mix.