I think that you just witnessed what high velocity magnums do by their nature. The faster you push the bullet, the more damage it'll do down range. You can use a tougher bullet like the Barnes TSX, Nosler Accubond or Hornady Interbond, but it's still going to make a mess. The managed recoil ammo is another option as it slows the cartridge down quite a bit and will be less destructive. Barring that, your best bet would be to aim a little farther back to avoid the shoulder altogether and make sure you only take direct broadside shots.

Mike