Sask has a minimum 24 caliber restriction on all big game. And while it is not an elk cartridge in my mind, it may work for some in other areas of the continent.
I like a bullet with some frontal area to put the hurt on the elk because it may only take 20 steps before dropping with a 243 but that 20 steps could be through hell and back.
I will stick with my 338 Win Mag they usually go about 3 feet after being hit, but that is sideways. If you ever have to track a wounded elk chances are you will never see him again in our forest up here.
My 243 is my go to coyote rifle