That`s interesting. Any numbers suggesting when that could happen?
It's really only likely in the case of very little wind. Spin drift is proportional to SG and also to TOF^1.83, and wind drift is proportional to (TOF - TOF_vacuum), so in the case where bullet BC, bullet length, and muzzle velocity maximize SG and TOF, while minimizing (TOF - TOF_vacuum), spin drift becomes most significant compared to wind drift.
As an example of when spin drift can matter, consider the 120 gr 7mm VM leaving the barrel at 2975 fps. In SAC, an 8" RH twist results in 20.4" of spin drift at 1000 meters. Each 1 mph of wind is responsible for 16.3" of wind drift, so with a 9 o'clock 1 mph wind the total drift is 36.7" to the right. But if instead you have a 3 o'clock 1 mph wind, your total drift is 4.2". So if you were to mistakenly assume a 0 mph wind, and if you don't account for spin drift, you could be off by nearly 3 feet of drift to the right. It's an issue similar to tolerance stacking, where if unaccounted for the small errors can stack up to create a large error.
