1) whether we like it or not, guns should run with ALL available ammo. Some steel case is terribly weak, and probably too low of pressure. Other than that crap, all ammo marked 223 or 5.56NATO must run.
2) a good CLP is what AR's seem to like. Mine also seems to like an additional drop or 2 on all sliding surfaces. That said, I like to run the trigger group a bit dryer. I flush it by throwing a few drops all over, wipe off as dry as I can get it. I leave the BCG fairly wet. They bore should be cleaned clean with solvent. Wiped dry. Then run a patch with CLP on it down the bore.
For CLP, I like Weapon's Shield. Break Free is a close 2nd. I look at all the rest with a distrustful eye. I clean the bore with Butch's Bore Shine. I forget the carbon cleaner I go after the BCG with on occasion. ...K something. I also have a tool for scraping the carrier and bolt.