Interesting video Devil, thanks for posting. A few years back I tried oiling the barrel of my Mustang between shots and got the same results - very small spread in velocities. I also got my best groups that way.

I have a suggestion though. The readout unit of your chronograph seems to be taking a pretty good beating by bouncing around when you shoot. Can't be good for the circuitry. You might want to set it on something other than the shooting bench.