All manufacturers quote G1 BCs for their bullets, only some quote G7 in addition like berger for example.
So, G1 is almost always the "native" BC in ballistic FTE... that said, the reason you never get a trajectory to work with published G1 BC`s, is because they always invariably publish the G1 BC @ or near a muzzle velocity typically somewhere around 2800-3200fps. The problem is that G1 BC`s are heavily dependent on velocity.
So when you shoot at something and notice your POI is low when using a manufacturers G1 BC, is because the bullet is continuously slowing down after it leaves the muzzle, and the manufacturer G1 BC no longer is relevant.
It is inappropriate
to use muzzle velocity G1 BC`s (for any bullet regardless of its shape) in a trajectory calculation because the appropriate BC to use is one that "cumulatively averages
" the BC over the course of its trajectory and the entire velocity regime which this encompasses
. Unless you have a cumulatively averaged BC, it wont matter which BC model you use in ballistic FTE, they will all be inaccurate...
Id recommend this site to learn more about it Home
and Bryans book which covers many subjects related to this matter.