I've killed them both w/ 3006 and 300 Win. 150gr out of the 06 and 180gr out of the 300. Shot placement still rules the show... However, a moose is a strange critter. Sometimes it goes right down w/ a vital shot and other times it takes it a while to realize it's dead. I shot 2 moose under 150yds. One folded, the other ran and hid for a while....
Long shots on moose, yep it happens. I put my Dad on a nice 6yr old bull, closest I could get him(oxygen tank) was about 500yds. I was glad he was packing his 300Win. Still took two shots to the breadbasket and the moose hung out for quite a while before deciding to die.