It depends. If we’re talking about the differences between a Spitzer and a Spitzer Boat Tail, ballistic coefficient can be ignored for ranges of about 250 yards and closer. The differences in trajectory between these two is just too slight to notice in the field, at least at these ranges. As the ranges increase, so does the advantage of the higher ballistic coefficient. This is why long-range shooters are always more concerned about using bullets that have a high ballistic coefficient.
