accessories

Just wondering how much ammo everyone stockpiles for the favorite calibers? I currently try to keep about 5000 rounds of .223/5.56, 5000 9mm rounds, 2500 .45ACP rounds and 200 rounds of .500 laying around. I really need to get that .500 stockpile built up more but its just so expensive. Not...

So the AR15 platform is pretty customizable from the looks of it. So far I've picked up a keymod rail, and am looking at getting some Vortex optics for it this weekend. Just wondering what else are the best/most common accessories for an AR15