The cow I took to a processor in Gunnison weighed an even 300# on the rail-field dressed, head, hide and legs off. She was a good sized dry cow.
With a pork carcass in that condition they say you loose about 60% of the weight....so if this ratio stays true with elk (300) / (.6) = 500 pounds. That's a mature cow but I would believe it.
I killed one in Montana in 2010 that I would bet was closing in on 600 pounds live weight, maybe more. It had a noticeably bigger body than any raghorn bull that I have killed.
