I've shot them with a lot of rifles, 243, 6mm, 30/06, 338, 7 RM, 300 WM, and 7-08...shot some with arrows too.
The last 30 or so, almost exclusively 7 RM or 7-08.
Mostly use the 7-08 these days.
Putting my 6mm back together after I get it back from pacnor...I reckon it will see some elk action by this time next year.
For straight up cool factor, the last elk I killed with a 30/06 was with my Dad's pre-64 model 70. My Grandfather, Dad, and I all have killed deer, elk and pronghorn in Montana with the same rifle...this elk completed the tri-fecta. My late Grandfather also shot a MT grizzly with it as well.