Crow hunter,
The boattail and crown can be perfect, and the flat-base will still be more accurate at closer ranges--say out to 200-300 yards, where most "short range" benchrest shooting takes place. This is because the boattail allows hot gas from the muzzle to slightly destabilize the bullet. This is why SR benchresters use flat-base or, at most, bullets with very short boattails.
Beyond around 300 the higher BC of boattails results in finer accuracy, due to less wind drift, even in very mild breezes.
