Barrel twist and length are also vital in determining crosswind wind resistance for pellets, while barrel twist direction has a different effect on crosswinds, although I don't see many LH twist airgun barrels. Longer and twisty are not always better. There is also the theoretical part of a ballistics app, and a single bc entered compared to two or more is still a guess, albeit an educated one. Dont forget environmental considerations too. The point is, without chrony data near and far and correct rifle/scope/pellet data you are still guessing. But i digress. To compare only one weight to another to say which one is more wind resistant than the other is almost moot IMO because pellet designs and physical characteristics differ with weight. The HN FT trophy for an obvious example. 14.6 gr and has a cone drilled into them to help reduce weight but it also changes the center of gravity a good bit towards the nose. This is totally different performing pellet than a crosman premier in the exact same weight.
Its not if one drifts less than another, just how much it drifts and is it consistent.