Spudgun

This is my first (and so far only) combustion spudgun.

Dimensions: combustion chamber: 75 * 450 mm, barrel: 40 * 1000 mm.
The mixture in the chamber is ignited by a piezo igniter from the camping store.

Even with hairspray as a fuel it is well capable of shooting potatoes over a distance of about 100 meters. The following pictures show the damage done to an old door with some old batteries as ammunition from a distance of about six meters:

The next thing I’m going to do is to search for a more efficient fuel. I’ve read good things about starting fluid, butane (for refillable lighters) and propane so I’m going to check those out.