How accurate my chrony is, I don't know. But what I do know is that with the same rifle, same chrony, same bullet on the same day the results were RL-17 200 fps faster than IMR4350.

62gr IMR4350 = 2900 fps (excellent accuracy, 63 gr shows pressure, perhaps slow lot)

63gr RL-17 = 3100 fps (same accuracy, more speed, no signs of pressure)