A drill piston is a dual use device. It serves as a base for a hand drill and is a firepiston. Look at the first image and the hole in the bottom of the piston is to hold a short piece of mullein stalk, a longer shaft is placed in the piston body and you have a handdrill. I have yet to make this work, but it is a neat idea.

Look at my original post on the handdrill piston to see the fireboard and mullein stalks.

Mike....see your PM's and thanks.