"Elk Hunting" is a statement takes in a lot of variety and difference.
Elk can vary from 200+/- lbs to upwards of over 750+ lbs. Those elk can be pursued on the back forty eating off hay bales in the flats, to public ground high in the mountains or deep timber.
Shooting relaxed elk on private ground where, if they run a bit is no big deal, is one type of elk hunting. A mature bull on public ground, during rifle season, in dark timber with no tracking snow is another type of elk hunt. And of course, there's all sorts of elk hunting in between.
While I have no qualm about a 243 on open country eating sized elk (or any elk for that matter), it's not something I'd chose for my own elk hunting. For me, a sensible minimum for pursuing mature bulls in timber is something like the 260 or 7mm-08. And, on big bulls, more rifle is never not a smart thing, unless you can't shoot it well, or don't want to pack it.
IMO, the "ultimate elk rifle" is a 22" bbl'd 338 WM shooting 210 Partitions at 2,950. I've taken bulls with that very rig and it works well. Ditto the 300 Mags and a 180 Partition. I just don't want to pack the rifles chambered for either anymore, so I chose much lighter rifles in more sedate rounds like the 270 or 308 Win. Big enough to break bone and penetrate from bad angles, but light enough to pack all day in the mountains.
For flat land hunting where weight isn't a big deal, and shots could be a lot further, I like more barrel/rifle weight. I've got a 300 WSM for that. 180 Partition, Ballisitc Tip, or Accubond at just over 3,000 fps is a lot of cartridge. Plenty for all elk hunting conditions.
But I doubt there's a better "every man's" elk rifle than the 30-06 loaded with a 180 Partition. If you can't get it done with that, it can't get done.
