For deer the accubond should work lovely. I have no experience with it on elk from a .277 though. However I have used a .270 to harvest both elk and moose previously with 150 Nosler parts and 140 failsafes. Another you could try is the 130 Barnes TSX. Either of these are proven elk takers and should workwell from your 270 wsm when elk are on tap.

As far as the Ballistic Tip advice, I agree for elk but for deer it has been my goto for many years in a variety of cartidges. I have never had one problem anchoring our larger bodied canadian deer when using the NBT. I am not sying it is a better bullet then the AB, but if it shoots more accurately and fits into your hunting situation...I would use it.

FWIW, I have used the AB to harvest deer, elk and moose in 160gr out of my 7mm rem mag...worked fine in all cases. I plan on loading some 140's for deer and pronghorn hunts this fall, if they prove good on paper. For elk I'll be sticking with 140 gr TSX which worked in 05' on a bull moose and elk to perfection.

Enjoy your new rifle