Does it compare to a 7mm mag performance wise and how does nock the deer down?

The 300wsm and 7mmremmag have very similar trajectories and will provide very similar performance on deer.Actually both are much more powerful than required for deer but both will also do a great job on larger game such as moose or elk.

If you hit them right, the 300 WSM will knock deer down about the same as a 308 or 30-06 they all shoot a 308 caliber bullet with more than enough ME for deer and most members of the deer family. I just returned from a Mule deer hunt where I dropped six mule deer with six shots from the 270 with 130 grain Federal Fusion loads. The shots ranged from one at 50 yards to one at 225 yards. One went about 50 yards (lung shot) one went about 20 yards. (Heart shot) the rest went down in their tracks. Neck and high shoulder shots. I prefer anything from the 250 Savage on up for deer. I have no need of any magnum cartridge for deer. Just My opinion.