Bullet selection is fairly important. A good 100 grain softpoint, like the Sierra Pro Hunter or the Hornady Spire Point, is best. I have had poor results with Barnes X and Nosler Partitions. The 85 Sierra HPBT Gameking, as well as the 87 gr. Hornay Spire Point, are also good bullets if you like a little lighter pill. Try for a broadside lung shot and stay away from the shoulders.

I have killed six elk with a 6MM. Pretty marginal, IMO, but do-able with good shot placement and a good controlled expansion bullet. For deer, it is solid and reliable for the disciplined hunter.