The last 5 elk I have killed have all been with a .308 Winchester. Each required only one shot.
3 with 165 grain Sierra HPBT Game Kings,
2 with (gasp).... 175 grain Sierra Match Kings.
I cannot count the # of Mule deer that I have shot or been acting as guide/pack mule, and let newbies shoot, using one of my .308s.
It may not be up to the horsepower or premium bullet standards of some, but using a .308 has filled my chest freezer every year with meat. The little .308 pop guns have helped me fill some other folk's freezers who, due to age or financial situations, needed a helping hand.
Cheers All