I'm still disappointed that BC has to be calculated by comparison with data from another projectile rather than comparison with the subject bullet's performance in some "pure" situation � in a vacuum, for example.
Only a G1 flies like a G1. Only a B7 (if there were such a bullet) would fly like a B7 � and it'd fly like no other bullet. Therefore, any "calculation" of the effects of drag and gravity on any bullet's velocity and trajectory is a very rough approximation � an estimate that seems to offer more precision than it can deliver.
Comparing the performance data of subject Bullet A and subject Bullet B by the same calculus can be useful as long as we realize that both sets of results are imprecise estimates based on impossibly imperfect comparisons.
