I built this gun after being a little dissapointed with my last ball valve copper gun. I wanted to make something more powerfull. The piston gun is at least twice as powerfull as the ball valve gun. I got my insperation from destruction photos found here: http://galfisk.kaaven.net/gallery/index.php 8)
And here come the photos =) (all shots are powered by 100psi)


The gun itself and a 3d illustration I've made of the inside.

GGDT data for the gun

Marble shot through seven steel cans. The can are in order from right to left.

1.5cm particle board. The larger whole in the middle is made by an AA battery and the smaller is from a marble

Steel barrel being shot with a marble from 10m

Spread pattern of three marbles being shot simultaniosly from 10m away. The power of each individual shot is reduced though.

A 9V battery hit by a marble.

Power comparisson between the ball valve gun and the piston gun using same pressure.