golly gee wally I and my cousin must be lucky. he uses a 308 and has killed alot of elk in 30+ years here. he got a 380+ score with it in Utah a couple years ago.
I use a Sako 06 with 165 grain, core lokt, and have to date killed 5 cows, and 3 bulls not one had to be tracked.
and i have killed 1 bull and 1 cow with a 35 Whelen 258 grain bullet, it really put em down, but it's not for the timid shooter. Ouch..