T
Twud
Guest
Can anyone tell me why certain bullets' BC changes as the bullet slows?
Mark
Mark
Ballistic coefficient is a measurement of drag. It turns out that you can optimize the shape of a bullet to lessen drag only for a narrow Mach number region. So, depending on the bullet's shape, it will have greater/lesser drag depending on the velocity. Now if you could get it to change it shape as it changes (loses) velocity . . .
goodgrouper
tryingtobeabettergrouper
It depends on what drag function you use. There are many. Most of the more aggresive shaped bullets actually increase in bc further downrange as proven by acoustic screens and radar. Some flat based bullets when run on the wrong drag function in a ballistics program can appear to lose bc faster than it should.