As far as "anti personnel", I'm not worried about a long range weapon for that. I have arms for SHTF scenarios for what I would need, close up work. As far as a 400 yard rifle for hog and deer, you would be fine with a 16 inch barrel as long as you yourself was capable of the shot. AA makes some pretty good rifles. DNS touched on a pretty good subject about factory loads. Since this cartridge was specifically designed around the AR platform, the factory loads are fairly specific as well. I reload, my old man reloads, everyone in our family reloads. I don't think anyone in our family have bought more than a box or 2 of something new on the market for testing other than .22 ammo in many years. But I think with the 6.5 gren, I would probably start off with a couple of boxes of whatever DNS recommended for hog's, being he is kind of an expert with the round, and then make up some reloads for myself and customize them to my particular rifle.