On another thread Major Caliber suggested that the 300 WSM might be a lot better choice for Elk than the 7 WSM. I looked at the newest loads from Federal to see if I could make a direct comparison.
Federal Loads the 160 Accubond at 3120 in 7 WSM (mine average 3162 today), they load the 180 Accubond at 2960 in the 300 WSM. My experiance has been that the 300 WSM 180 loads are pretty much right at 3000, the 7 WSM exceeded factory specs in my rifle.
The 160 gr bullet has a higher B.C. and better sectional density than the 180gr. Though the 300 WSM starts with a little more energy at 300 yds the 7 WSM has 2380flbs of energy whereas the 300 WSM has 2375 -almost identical. After 300yds the 7 WSM 160 Accubond pulls away from the 180 Accubond as far as retained energy goes.
One could probably argue the 7's superior sectional density vs. the 30's greater cross sectional area without getting anywhere signifigant. But in the end the 7 WSM is a lot closer to the 300 WSM than the 270 WSM, and even outperforms the 300 WSM energywise past 300yds with identically constructed bullets from the same manufacturer. The difference is even larger when comparing Federal Loads with the 160 & 180 Partitions.
I think either will work great on Elk and hope to try........DJ

I have no doubt either will work just fine. The arguments one can make for either round is basically just splitting hairs, they are a lot more alike than they are different. The math don't lie, they both have decent weight and frontal area, good velocity, great bullet designs, and efficient cases. Any good shooter would do fine with either of them, IMHO.