I was surprised a month or two ago to get the newsletter from Sierra and they said that their "tough" bullets are their Gameking HOLLOW POINTS! They stated that their hollowpoints for rifles are just the opposite of their pistol bullets, in that the HP's are tougher than the SP's whereas in pistol bullets, the opposite is the case. Note, though, that they are talking about the Gameking bullets and NOT the Matchking bullets. My experience with Sierra bullets has been limited to the softpoints, and while good for deer, they seemed a little "soft" for the tougher game. A 150 gr Sierra SP at 3200 fps would seem to be asking for jacket separation, since they are designed more for a muzzle velocity of 2900 fps from a .30-06 or .308. But that opinion may be worth just what you paid for it.