RE: Elk: Recommend .270 or 30/06 hot/flat-shooting ammo?
Here is something to look at. There is only 4" difference in drop at 500 yards between 150gr and 180gr rounds but you gain 200 ft. lbs. of energy at 500 yards with the 180gr round.
http://www.remington.com/products/ammunition/ballistics/comparative_ballistics_results.aspx?data=PRA3006A* PRA3006B*PRA3006C