Hi drpbroun5,
Thanks for asking. Instead of accepting a reply from those who have never used GSC on game (at any distance) rather take the advice of those who have. You ask "How do they fly (BC, accuracy, etc) and what sort of terminal effects have you seen on deer and elk at high as well as low velocities?"
Well, GSC bullets are deadly accurate, easy to do load development and so uniform from batch to batch, that you do not have to redevelop a load once it is done. You will find that the barrel of the rifle runs cooler, is easier to clean and throat erosion is far less than with other makes.
The cherry on top is of course that the window of application is far wider with GSC. You will get a double caliber mushroom as low as 1600fps impacts and, should you bump into a game animal at point blank range, it gets the job done as well. Solid reliability at any speed and no surprises.
We give a calculated BC on our website. Unfortunately the bulk of people average the numbers and come up with a BC that is completely unrealistic. To rectify this, at the explanation of the BC numbers and the speed ranges we give for them, we have added the following:
"BC values are calculated at standard Metro values using a G1 profile. Any comparison with the BC values of other manufacturers is not valid as there is currently no standard method in use between manufacturers. Enter these values into an external ballistics program to calculate BC for your launch speed and distance. For exact values, shoot drop tables at the elevation and temperature for your location."
A comparison of all the factors that make up a good hunting bullet is very welcome.