spud gun problem

[guitarfreak]

i have a metal spud gun that doesnt want to fire. the barrel is about 1 1/2 feet long,and about 1 inch wide,while the combustion chamber is about 3 inches wide,and 1 1/4 foot long. the ignition is a gas fireplace peizo ignitor wired to a spark plug out of a car,screwed into the body. i got a couple of good shots out of it,then it refused to work,even using the same amount of fuel. i want to make a camera ignition,would this solve the problem? or is it a fuel mix problem. oh yea,im using lynx deodorant.

[PCGUY]

Is there any kind of gunk building up inside the chamber that may be preventing the spark plug from sparking correctely?

[taterjim]

I would start by lessening the fuel mix ,if that doesn't work change the sparkplug(get a tuneup)a three ft. barrell would get you more distance on your shots.

[guitarfreak]

i am going to upgrade to a camera ignition today,the old spark was pretty feeble anyway.there isnt much gunk;the advantages of a metal cannon is that you can just hold a long reach lighter to the combustion chamber and burn off the crap it saves alot of knuckle scraping

[guitarfreak]

i got it working!!! i cut the outer electrode off the spark plug,and put a blob of solder on the inner electrode: for some reason,it now shoots consistently first or second click. i couldnt be bothered setting up the camera,but one day......