I like 55 gr and 62gr ammo. I have some heavier stuff for hunting, but then again, I have rifles for most specific size game, and the .223 is a dog and cat bullet to me. (And piglets.)

For my plinking, and carbine shooting; Wolf/ WPA. It is 99% as accurate as xm855 and it cycles cleanly. At $190 per 1k rounds, I can afford to shoot a LOT with it. Yesterday with iron sights, my son took a 'yote at 170yds with the 55gr WPA in a DPMS carbine, no frills. It absolutely bowled the dog over, while trotting off at med. speed. The ammo is accurate enough unless you are going to try for less than MOA target shooting.