SpudFiles

Okay im gonna build a first combustion spud gun and im wondering if these specs sound good, a 4-5 foot ish barrel of 2" and a about 1' chamber of 3", a BBQ igniter for ignition and whatever i can get at a dollar store that will work for fuel. open to any suggestions that may make it better cause i havent got any parts yet!

You would need about a 2 foot 3'' chamber or it wouldn't have enough power to push the tater out the barrel. you could have 1 1/2 foot 4'' chamber. other than that, ya it sounds good, thats about the size of mine.

the barrel would be a bit long because for a good Chamber:barrel ratio should be optimal .8:1 but for a nice muzzle flash and big bang a 1:1 works nice. so you could make your chamber longer or your barrel shorter.

nextly add a chamber fan they make it so much easier to clean the chamber so you dont have to run around with a spud gun over your head just to clean the chamber after shots and it also mixes fuel better resulting in a faster combustion that way it reaches peak pressure while the projectile is still i the barrel.

finaly make sure you put some kind of netting (wire of some kind) inbetween the chamber and barrel so projectiles like ice or something you drop into the barrel by mistake dosent fall into the chamber crushing the chamber fan

use the 1.5:1 c:b ratio by vloume

volume of a cylinder : pi x r^2 x hieght(length)