If I do a psi gauge and pipe what psi would I use

i covered the holes and put fuel in...i keep hitting the igniter and eventually it fires and wow!!! now i think i need to make the spark bigger and just get the right mixture

ok thanks i will try that... but what about the hose position question on the nozzle cover the vent hole or not

ya ur prob right ...and i do vent after each shot ... also i have the hose connected to the tip of the propane nozzle but i did not cover the holes that mixes it with air in the nozzle should i slide the hose all the way on???

hey guys i decided to build a cannon to mess around with while in maine for the week launching crap across the lake... it was a quick and free build i used a 3 in chamber and 1.5 barrel,, barrel lenght 4ft and chamber lenght 18, i used propane as fuel ran a hose to the tip of the propane into a barb...