so i recently built a great ar15 and am having a difficult time selecting a decent 5.56 ammo to stock up on for shtf stash. 5.56 tap is out due to avalibility and cost. i dont want a 223 load because the 5.56/223 round is so dependent on speed for terminal proformance. so basically what im looking at is mk262 -(clone,not real thing but pretty damn close) and mk318 ( real mcoy). both i can get for 75 cents a round or a little less. just cheap enough to run a few hundred through my ar n stash 500 for what ever. i want something more substantial than m193 and m855 so please if any one could give me opinions on mk262 and mk318 sost i would be forever grateful. 16" barel 1/7 twist.