spud gun help

[aaron1023]

i built a generic spud gun and the thing shoots like ten feet. once out of like 30, i got a loud good shot... but the potato didn't even come out. please help???

[starman]

i built a generic spud gun and the thing shoots like ten feet. once out of like 30, i got a loud good shot... but the potato didn't even come out. please help???

Aaron, we'll need much more information about your gun before we can help you...some pictures would be very helpful as well.

Is it a pneumatic or combustion, how big is your chamber/barrel, what you using to trigger it, what fuel etc...

[aaron1023]

combustion, barrel: 2ft and 1.5", chamber: 1 foot and 2", i use a lantern igniter, and tag body spray

[drex]

you used a lighter? do you have a hole drilled into your chamber? if so the combustion gas could escape threu the hole.

[starman]

That's smallish chamber...hard to get to fuel mix right in those. That you get 1 in 30 shots tends to point to fuel mix...you're either too rich or too lean...my guess would be rich. Experiment with your fuels.

Maybe consider a 3" chamber instead of 2" if you keep it a spray and pray.

[aaron1023]

no i drilled a hole and sealed a lanten ignitor( a flint wheel)

[drex]

oh
i thought you ment a lighter that one could use for lighting candles or lanterns.

[aaron1023]

i've tried shit like blowing in the chamber, only spraying for like a second... i mean what really works

[mega_swordman]

If you are getting the noise but nothing coming out of the barrel, I would assume the problem would be a bad projectile in the barrel since the noise should be some indication that it is still firing and pressure is coming out of the barrel.

[aaron1023]

it was air tight basicly... is that bad

[drex]

no, as long as it isn't to tight so it could not buge when fired.

[aaron1023]

i think im just going to make a new gun.... whats an easy gun to build

[starman]

i think im just going to make a new gun.... whats an easy gun to build

Browse through the cannon showcase....find something you think you can handle and go for it. Do as much on your own as possible, if run up on a snag, ask away.

[Darkside 6ix]

lol, That was an easy gun that you build. Try lubing up the barrel with some jelly, Petroleum jelly that is =]

[Biopyro]

Maybe you'd prefer starting with a ball-valve or unmodded sprinkler pneumatic. They fire every time, and are suprisingly powerful if they are standalone, because it makes it easier to open the ball valve quickly.
There are a lot of simple pneumatics around, amongst all the less simple ones. Have a look at Instructables