Here ya go:

"Arrow Speed Chart from Eders Magazine:
Looking to discover how fast your arrows are shooting but don't have access to a chronograph? Well it's easier to figure out than you might think:This simple table will get you in the ball park. First, shoot your bow at a target from 20 yards using your 20 yard pin. Mark the center of the group. Next, shoot at the same target from 40 yards, aiming at the same point, but again using your 20 yard pin. Mark the center of the second group. The distance between these two marks will tell you your approximate speed.Distance between 20 and 40 yard groups (inches) Approx. Arrow Speed (fps)
28.7 = 220
24.2 = 240
20.6 = 260
17.7 = 280
15.5 = 300
13.6 = 320
12.8 = 330"

Hope this helps get ya in the ballpark. Be safe.
Shoot Straight
Derbytown