Re: Bullet weight, velocity and energy???
Generally, while energies can be equal between lighter and heavier bullets by varying velocity, many prefer a heavier bullet for larger, and thicker skinned game. The heavier bullet's increased weight, heavier construction, and sectional density will better maintain energy upon contact with heavier game, and give better penetration, particularly on angled shots, or when bone is encountered. With a strongly constructed bullet , the difference may be less apparent at shorter ranges, but at the longer ranges the heavier, higher BC bullet can better maintain velocity, and produce the same or increased energy and velocity. This is why you see the heavy high BC bullets being used by LR shooters. The advantage of the lighter, faster bullets is the reduced drop, but many will make the trade off for better killing power, particularly since bullet drop a known variable that can be compensated for, and less critical on larger targets. I think your inclination to go with a 180gr bullet for elk is right. IMO.
"Let us speak courteously, deal fairly, and keep ourselves armed and ready"-T. Roosevelt