I have only taken 9 elk in my lifetime, so not an expert by any means. 7 of those were with a 270 and 150gr partition, the other two were with a 30-06 and 180 Hornady spire point. all 9 were once shot kills with the longest being around 300 yards and the shortest 75 yards. as far as being dead, I could not tell the difference between the two calibers. I am always somewhat amused by forums when this question is asked for two reasons. One is why we all seemed interested in the smallest caliber and the other being the insinuation Elk are made of steel and concrete. more important to my limited experience are perhaps angles of the shot and distance. my elk hunting days might be over now, but if I did go, I would not hesitate to take anything from 243 up with the right bullet and the understanding I have to pick my shots.