There is a slight advantage to a larger cal. when it comes to wind drift...but not much. I ran a comparison on a ballistics program between a .45 PRB and a .54...at two muzzle velocities 1400fps and 1800fps. At 100yds, 1400 fps,10mph wind drift for .54 was 10.4", for .45 12.6". At 100yds, 1800fps,10mph wind drift for .54 was 10.9"; for the .45 cal. 13.5". You be the judge if a couple inches is significant. An interesting fact is that at these velocities (and higher) The drift increases slightly with added velocity. Sooooo.... adding more powder doesn't usually reduce wind drift. Drift is more closely correlated with velocity loss than time-in-flight.