The fire piston is a unique method of creating fire, using nothing but compressed air to ignite tinder.
A plunger is quickly pushed into an air-tight tube, compressing the air, raising the temperature, and igniting a bit of charcloth or other tinder set in the tip of the plunger.
The key requirements for a fire piston to operate correctly is a straight, smooth bore and a plunger that seals the chamber air-tight.
Fire pistons are commercially available with an emphasis on the artistic rather than the function. You can create your own from scratch or purchase a kit to assemble and carve.
See Wilderness Solutions for a kit.