Its'd better to have your chamber have more volume then your barrel, IMO.

I bought mine at Canadian Tire for $15.

Sounds like the one I just built only my cannon has a 16.5" long chamber and is "inline".

Direct injection is into the actual cylinder itself (diesels and the experimental "gasoline" diesels use it.). Actually some advanced/efficient two stroke engines have a direct injection. Indirect (not very familiar with the term, but most likely...) are the injectors that inject fuel into the intak...

I might try this.. What im thinking is placing a little flour in the chamber, close the plug shake'r up and try to ignite it lol i dunno.

THIS PROGRAM IS FREAKIN SWEET! Thanks for the link and tips!

I agree with starman that 300 yards is unlikely - the mass of the potato vs. it's size is just not high enough. They tumble and slow down a lot after leaving the muzzle. Nevertheless, they can and often do go 200 yards or perhaps more. For fuel, I've had great luck with Static Guard. It takes about...

Whats that program called? I googled it and nothing came up.

check it: http://www.spudfiles.com/spud_wiki/inde ... rrel_ratio

Sorry yes sabot with the "t".. :wink: No a 1.2:1 will still have fine performance. .5 to 1.5:1 is a good performance window for most combustion guns...spray and prays aren't as predictable though...too many variables in play. Still these numbers will hold for them as well. Keep in mind the first nu...

Sabot, thats it! Would pure methanol do well? The big reason for me cutting the barrel down, is the size of the bloody thing, lol. It goes from he back of my trunk, through my rear seat (folded down of course), and up to my shifter! Knocking 10" off would make alot of room but would bring the C:B ra...

It is? Must be the fuel im using then, cause a rock with a plug (Whats the plugs called that you put behind a projectile to make a better seal? Sry for my ignorance :lol:) will fly about 100ft. Thats the best I've gotten so far. Thats with Rubbing Alcohol though. I think that anti-static spray will ...

Sry to double post..BUT I think I found why my cannon isnt performing up to "par". Right now I have a 1:1 C:B ratio. Cutting 15" off the barrel, I will achieve .7:1!! Think it'll perform better? I'm also going to try out anti-static spray, sometime this week. Let me know what you guys think.

lol, I read a topic of one in a 4-wheeler forum, and built my own design that I though was strongest. First type I built was a pnuematic.

Age 15, ok, that is at a point where your parents did not "control" you right? Not at all. My parents merely asked that I let them know what I was doing. My dad knew what spud guns were and didn't see any problem with them as long as I was safe about it. I started shooting guns when I was 7, and he...