Snap Fit Mini Crossbow. Thing:964321

This is the item on
http://www.thingiverse.com/thing:964321

I also mod it with a metal pin so that it stops abruptly
I also coat the track with embedded graphite.
It fires cocktail straws like a bullet..

assemble:
https://youtu.be/NY1hMB8PkSU
shooting test:
https://youtu.be/LSkBBMnThuw
shooting test 2:
https://youtu.be/sfzaFVzgkzs