http://web.archive.org/web/20060621090408/http://www.geezers-corner.com/GeezersCorner/backdraftx.html

We experimented a bit trying to make a better blowgun for our nerf darts. Even tried some TPU versions. This one was based on some readings we found about building a backdraft blowgun. Didn't work as good as we had hoped, but was still pretty fun.

A previous version we read about had a cap that would pop off when you blew with enough pressure and after the cap would pop off it would should the dart out with the release of pressure.

This fits the darts perfectly to cover up the opening with your finger and blow to build up pressure. Then when you release your finger it does shoot out way better than when you just blow normally. Fun either way though.