I prefer bullets that are heavy for caliber (S.D.) So I would probably choose the 180's. Now thats assuming that your rifle will shoot them reasonably.Don't concern yourself with whether or not they are "overkill" for whitetail. Dead is Dead. Use a load adequate for the moose and I assure you that it will perform fine on the whitey and caribou

Rifles are pecular in that some have pet loads that they will shoot and nothing else. My 338 will only shoot handloads of hodgdon 4831sc and nothing else. Its a tack driver with it and below average with other loads I've tried.

I would try to stay with a quality bullet like the x bullets, trophy bonded, or partitions if I were you.You will most likelyfind thatyourrifle will like one bulletover the rest.My friends 221 fireball (varmint cal) shoots sierra varminters into little holes but spreads out to 2"with nosler balistic tips; go figure.

When testing your loads don't worry about rezeroing. Justaim at the bullseye and look at how tightly they are grouping. Once you find the load your rifle likes then you can rezero for that load.