Miller,
While I agree that 50mph is pretty fast for a clay, there are a number of birds that fly 60 + mph. Routinely, pigeons fly paralell near my truck at freeway speeds. The Calif Valley quail can fly well above 50, probably more like 60 and up. I've seen chukar that I'd estimate were coming downhill (their favorite direction) at probably 70 + mph. These are all just estimates, but I did sleep at a Holiday Inn Express. Back in my RC model airplane days, my good friend bought a radar gun, and I also had a telemetry device which included airspeed among other data. So, I have some perspective, although admittedly eyeballing speed can be pretty far off. It'd be interesting to irradiate a few wild birds for real data.
