Lever action .30-30 or an SKS. Fairly simple, reliable, hit reasonably hard, light.
SKS is not light, compared to an AR15 or M4. A good lever gun is an excellent option, however. I favor the .357 version since it has much less recoil and therefore allows quicker follow-up accurate shots and is effective out to two hundred yards for kills. Ammo is lighter (a sling with thirty rounds in it is much lighter in .357 than the 30-30). The ability to feed a handgun and rifle with the same ammo is also a plus for the .357 lever gun.
HOWEVER, for use around the compound and SKS spitting 7.62 x 39 is hard to beat for impact, cost of tool & ammo, and reliability.