When readng these replies and all the complaints of how there is soooo much dead space(exagerate), I got reminded of one of my old projects I had abandoned. It is very similar to this one, but insted of the dart stopper right behind the dart when it gets dropped in, it's right infront of the plunger. I am not sure if it could work in this application as the lever can only travel a certain distance, but it can be something to experiment with.
Here's a picture I quickly drew up...
EDIT: After watching the video again, I realized that the rear bolt thinger is what loads the dart into the barrel, but if you were to swap out the rear moving bolt to a stationary bolt, and use the barrel to lock in a dart, then that should also drop some dead space.
Edited by rokor, 30 January 2009 - 08:42 AM.