what is the difference between g1 and g7 ballistic coefficients?
G1 vs. G7 Ballistic Coefficients — Which Is Right for You? G1 and G7 refer both refer to aerodynamic drag models based on particular “standard projectile” shapes. ... So, when choosing your drag model, G1 is preferrable for flat-based bullets, while G7 is ordinarily a “better fit” for longer, boat-tailed bullets.