Here's a site with videos of various weapons firing, filmed at some ridiculously high speed. You can actually watch the projectiles leave the muzzle, the action working, etc..
http://www.bsg-dornier.de/schiessen/index.html?/schiessen/filme/filme.htm
Thanks to Liberty_MI at SomethingAwful for the link.
http://www.bsg-dornier.de/schiessen/index.html?/schiessen/filme/filme.htm
Thanks to Liberty_MI at SomethingAwful for the link.