Understood, and yes, my goal is to have my bullets above Mach 1.2 at the target for the reasons that I explained in the other thread. However even in the supersonic flight regime, the BC value for the bullet changes and you can see that at the Sierra website. I think the G7 value is more a deterministic and simpler value to use for all (supersonic) velocities and I have calculated the G7 BC for the long range bullets I use following the rather intense formula in Bryan's book and that's what I use for my trajectory charts at the JBM site, of which I have been a long time user.
