A lot of bullets would work. One of the virtues of the 6.5 Creedmoor--and 6.5x55, 6.5x57 Mauser, .260 Remington, which are peas in the same ballistic pod--is that many cup-and-core bullets will work on game larger than deer due to their moderate velocity. But from personal experience I would tend toward the 120 Barnes TSX and 127 LRX, 125 and 140 Nosler Partitions, and 156 Norma Oryx, but other controlled-expansion bullets would work as well.
The one bullet I would NOT recommend is the Hornady 160-grain round-nose soft-point. Have seen it break both shoulders of deer and exit--and fail to reach the opposite ribs on broadside lung shots, when started at 2200 fps from the 6.5x54 Mannlicher-Schoenauer. (Phil Shoemaker had the same sort of experience.)
“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.” John Steinbeck
