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Uncklenick, good post on the spin drift curves increases with each range segment down range. One of the Sierra ballisticians (Bob McCoy?) mentioned some years ago that it's almost a tiny percentage of the trajectory curve but at right angles to it. Not exact, but close enough to see the horizontal path wind drift takes.
I believe that if your load has a 10 inch spin drift at 1000 yards, get a windage zero in still conditions at that range then move your sight 1/2 MOA to the right. Then you'll never be more than 1/2 MOA off exact at all ranges up to 1000 yards. The shorter range gets, the smaller angular error there is. And the error will pass through zero about 2/3rds downrange,then be a bit to the left back to the muzzle.
Nobody I know of can estimate corrections for cross winds faster than 5 MPH for a target 1000 yards away with no more than a 1/2 MOA error.
Use ballistic software to calculate the sight elevation settings for zeros at different ranges for different head and tail winds, too.
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