SpudFiles

hi guys i was searching around the web for airgun stuff when i came over this website and this tool that somebody has made to make rifling i was just wondering if anybody has ever seen this before. i dont know how it works at all so if anybody has any ideas i would love to hear them.
Ling: http://www.airgunhome.com/agforum/viewtopic.php?t=8710

nobody understand how this works???

It Forces a Cutter down the tube, using the tube with the spiral as a twist guide.