Let me tell you that this article came as a huge surprise. One day, out of the blue, a lengthy, detailed analysis of airsoft round velocities shows up in the staff mailbox with a modest request that we 'post' it.
Reading through this thing took some time and some significant noodling. I should warn you that this isn't some lightweight fluff piece-- it reads a bit more like a college thesis. Not that this is any surprise: the author reports that, in additon to being a member of The Covert of Canton airsoft team, he holds a BS in Engineering and works in the Aeronautics industry.
Curious? Take a look at what he's got to say on the subject of FPS, Weight and Velocity.