he should use a layer or two of tin-foil as a seal, inside the device… tin foil, as well as being air-tight and water-tight, will rupture at a certain pressure in such a way as to remove itsself from the path of the volume of steam as it leaves the device… then there’d be no need for cork.

What is the point of the potato if he is shooting the cork?

Nice. I like the integrated design but the pressure buildup is because of the cork and not the potato. If you could build up the vapor pressure in a chamber, then release it all at once against the potato, then the potato would fire on it’s own otherwise you would just have a potato chunk slowly eject itself from the end of the gun as the pressure builds up.

With this half Rotten Potato its twice as Lethal.. Well at least once.

It won’t take much water at all because when water flashses to steam it expands into 1600 times the volume it was before.

1 drop of water = 1600 drops of steam. Neat project. Now it’s got me thinking of a way to vaporize all the water INSTANTLY. Then you’ll get a powerful gun.

I can’t remember the site, but a fast way to make steam is to use a capacitor bank to flash boil the water in a chamber. The nice thing about doing that is you don’t need a pressure seal as the water rapidly changes to steam. The downside is the capacitor bank needed can be large and deadly in and of itself.

I believe it’s refered to as electro-thermal and you can find a bunch of videos on youtube.