I made a spudgun (Pics (56k, dont come near))

[LathanStanley]

gasoline?

[Neddie]

Not good enough... you want something that burns easier, quicker, hotter and is a lighter compound.

[Comp1337]

Gasoline works excellently, but it is very very picky about how much you use. I meter it with an old syringe at the moment which works to satisfaction though. Another downside is that you need to wait until it is vaporized in there, which takes a while (my fan speeds this up quite a bit) It is however way cheaper than axe/lynx, which is why i use it some

And hydrogen from hydrolysis would be perfectly mixed with pure oxygen, which gives way too much power for my poor gun Even separated it would probably be too powerful :/

[maverick256]

Well, you don't want the propellant to actually explode, but instead burn. Explosion will give a sudden kick of pressure that actually isn't that effective at transferring energy to your projectile (but instead very good at blowing your gun up). Burning, on the other hand, gives a much more even and smooth pressure curve which the projectile can use more effectively. Premixing hydrogen and oxygen is such a bad idea because it'll explode and just blow your gun up instead.

I'm just pointing out the obvious though. Cool gun :)

[SwiftSpear]

Well, you don't want the propellant to actually explode, but instead burn. Explosion will give a sudden kick of pressure that actually isn't that effective at transferring energy to your projectile (but instead very good at blowing your gun up). Burning, on the other hand, gives a much more even and smooth pressure curve which the projectile can use more effectively. Premixing hydrogen and oxygen is such a bad idea because it'll explode and just blow your gun up instead.

I'm just pointing out the obvious though. Cool gun :)

If the gun body is strong enough exploding is ok... The energy has to go somewhere, and that somewhere is gonna have to be the potato. You might end up with shreds rather than a projectile though.

[Comp1337]

Well, you don't want the propellant to actually explode, but instead burn. Explosion will give a sudden kick of pressure that actually isn't that effective at transferring energy to your projectile (but instead very good at blowing your gun up). Burning, on the other hand, gives a much more even and smooth pressure curve which the projectile can use more effectively. Premixing hydrogen and oxygen is such a bad idea because it'll explode and just blow your gun up instead.

I'm just pointing out the obvious though. Cool gun :)

If the gun body is strong enough exploding is ok... The energy has to go somewhere, and that somewhere is gonna have to be the potato. You might end up with shreds rather than a projectile though.

Maverick is right, the general consensus among the spudgun community is that detonation is both dangerous and inefficient.
Also afaik hydrogen and oxygen will burn, given that the mix is blended well enough and you have a single point of ignition

Me and my mate (LORD_WILLE, some of you may know him from the lobby) did a small field test of the gun yesterday. We shot a potato almost out of sight :) We estimate a range of ~250 meters, and thats with a bit funky fuel mixture (Tis damn hard to meter aerosols >_<)

[CompWiz]

I am also planing to build a produce accelerator,

but I'm busy building a Tesla coil...

[Keithus]

Pneumatic spud guns ftw. And hybrid spudguns if you feel like killing yourself.

[SinbadEV]

My dad's potato cannon used a madified BBQ ignition button... it gave the thing a trigger.

[espylaub]

Two.
Hundred.
And.
Fifty.
Meters.

Jesus.

[Comp1337]

On the topic of building cool stuff, Ive found (and ordered) the most awesome book ever
Electronic Gadgets for the Evil Genius