I have to say I do NOT get the mindset that grabs a rifle in the house. Maybe my house is just too small but I prefer to have a gun that won't round corners before me and make its self a great handle for the zombie. I can hit just fine at the range my house provides and my Glocks all have night sights. They can also be held in one hand so at close quarters I can wield a flashlight, hammer, knife, skillet or light switch as needed with my offhand. Try close quarters combat in a dark house with your AR in one hand. Behind my hand guns is my 12 gauge with pistol grip and 18 inch barrel. Even that is too long but it sure is comforting. I'm not saying I WANT to be grappling with a zombie in my living room, but if one pops up like a rabid whack-a-mole I want to be able to stiff arm him with one hand and fill him fulla lead with the other. And AR at the bend in the hall ain't gonna let you do that.
Oh yeah...the 40 S&W is GREAT for get-off-me shots in the dark too. At least you don't have 3000 FPS rifled slugs zipping thru walls killing the wife and kids while you blast away at a zombie behind the couch. Rifle in da house! puhLEASE!
Yep, thats my go to home defense weapon, 12GA with pistol grip...i practice manuvering around my house and slicing off corners all the time, can get around and manuver the pistol grip shotgun as well as a handgun, takes practice.