I've killed about 10 whitetails with a .50 round ball. A few dropped on the spot (brain or spine hits), but most act very similar to archery kills. The animal shows little or no sign of being hit and runs off. There is usually some hair and/or small blood splatter on the ground where it was hit, with a blood trail starting 20 or 30 yards later. The blood trail gets progressively larger and the animal is down 50-100 yards away. Most of the time the ball goes through and through, but a few didn't exit and were found up against the hide on the far side. There's very little meat damage - you can "eat right up to the hole".
I'm happy with those results on deer. I'm sure they'd work on elk, but I think a conical is probably a better choice.