The 300gr SMK isn't just a target bullet because it has a thicker jacket than a 30cal bullet so the expansion characteristics are different than what we're use to seeing. They label it as a 'target bullet' but imagine jacketing a 240gr 30cal bullet in a thicker jacket, then making it hollow point and adding another 60 grains. You'd have yourself a pretty hard hitting big game killer.
A buddy of mine has used SMK's hunting a lot and has taken numerous elk and moose. His reports are that sometimes they pencil through and other times they tumble. They always provide a quick kill due to the size and energy involved but expansion doesn't happen reliably.
His results are one of the reasons I switched to Berger Hybrids.