Actually, in some states it can be easier to obtain hunting rifles than sidearms, which IIRC, the Zombie Survival Guide states are superior. In the first place, the primary advantage of most military rifles is their rate of fire, which is not a concern with zombies, who are slow moving, don't seek cover and easier to aim at. Getting several rounds in the torso, though efficacious against people, does nothing to zombies. A single, well-aimed shot in the head from a bolt-action hunting rifle is more effective than an entire magazine from an AK-47 sprayed in its general direction. Neither is the AK-47 as accurrate as most hunting rifles, and M-16 variants are supposed to be high-maintenance weapons, especially for untrained civilians. And of course, there is the issue of the high ammunition consumption for automatic weapons. You have to CARRY ammunition, and it is mostly made of metal. A box of cartridges the size of a brick is a bit heavier than a brick. So imagine you are carrying a backpack full of bricks, or else imagine you can fight the zombies for maybe three seconds before your rifle becomes a funny looking club. Still like your chances? Stick with civilian weapons that are more easy to use, supply and carry.