I would rather have a 168 gr bullet with great shot placement than a 180gr with poor placement. Shoot what you feel good with according to recoil and shoot what your rifle is more accurate with.
I believe many people get book wise on Sectional density numbers and ballistic coefficient numbers but are not skilled in the field. I refer
to people like this as Barr stool knowledge.
Think about this a high BC bullet in the hands of a Bar Stool, know it all shooter, making a 100 yd shot and hitting a animal in the guts. Greatest whiz
bang bullet that all the internet forums and magazine writers are talking about. Gets the bar stool, know it all people recommending it and a animal without a clean kill.
Old school Bullet out of a smaller rifle and a woman or child shooting the animal right in the heart or vitals....Which do you think will get the job done better.
Get the best bullet you can but don't rely on the numbers and bar stool knowledge to make your decision for you.. By the way I really like the Barnes bullet and the Accubond if the rifle will shoot them.