A good carbine is something any zombie survivalist would love to have slung to their shoulder when clearing a location, or moving though the tight urban ruins. Most carbines are chambered in the 5.56mm NATO round (the classic bullet used by the M-16), but in recent times many have felt in a carbine with the shortened barrel, the 5.56 doesn’t have the punch that it usually has when fired from a longer 24 inch barrel. Enter the 6.8mm Special Purpose Cartridge (SPC), delivering 44% more energy than a 5.56 NATO when fired from the same barrel length (16 inches), the six-eight gives you the power you need to put rounds through zombie skulls, even if you have to get through the wall in front of you first. The Bushmaster 6.8 SPC rifle uses a slightly modified magazine and upper receiver to allow you to fire the 6.8 SPC from a familiar weapon system (the M4/AR-15 framework), reducing your learning curve when the z’s pile up at your door. the Bushmaster 6.8 SPC has a 16 inch M4 profile barrel allowing you to move through cramped areas and still bring your weapon into play. Plus the 6.8mm gives you more power than the 5.56 NATO, but is still far more controllable than the 7.62mm fired from heavier rifles.