That pneumatic seemed to have more power, thanks for answers but keep writing all you guys know about those cannons, it can be helpful for others to decide what type they should build.
And what speed can i get in a pneumatic or combustion, Meter per second?
I saw a AK-47 reached 700m/s

I have built a mini combustion but it was crappy power so now ive found a small 13 bar tank and going to build a pneumatic with that. We got a really huge compressor at home that loads 14 bar or 196psi. But i wonder if i put one of those quick conectors on my tank it will leak some air when i realea...

What is the major difference? god and bad? in two same sized cannons

oh yeah! i never thought about that!
why do a cannon that runs on expensive gas when you can run it on air.
thanks guys

hmm that sucks.. So i cant make a more powerfull cannon that can shoot small projectiles. I better get som more of that black powder

yeah, but i want to shot small hard projectiles and no potatoes

thanks for the answers! Then i have to build a bigger combustion chamber but with the same small barrel and i will get those 3 apples

I welded a spudgun about 30cm long with the barrel. i use a BBQ igniter wired with a sparkplug. I sprayed som butane/propane refill and loaded with a little sharpened bolt with tape around it to make it air tight, then i shot at a apple and it only went about half way throug. earlyer i made a little...