Thread: Explain why please

Originally Posted by Old Bastard

I see the Ballistic Coefficient is different 160 gr is .330 and the 140gr is .277 .What determines the coefficient I would have thought that the projectile would be identical in shape etc only different weight ,but as I say I know nothing about ballistics

3 things determine the BC (courtesy of Mr Litz)

WEIGHT: The heavier the projectile, the higher the BC, because a heavier object penetrates air better than a light one
CALIBER: Cross sectional density - a narrower bullet penetrates air better
FORM FACTOR: A measure of how streamlined the bullet is. It compares the projectiles drag to a standard bullet. The most common "standard" bullets are the G1and G7 shapes.