You have a good combo of powder and bullet to start with. Most reloading data listed is for 223 Rem data, which max is about 55K psi. If your AR is 5.56, it is rated at 62K+ psi. You can load to the higher 5.56 pressures, and it will generally shoot better. Loading to 5.56 with 223 Rem data equals about 1 to 1.5 grains more powder. BLC-2 is a slow burning powder for 223, but it should work fine in your application if you load up near max. I wouldn't plan to use lighter loads with this combo. And use magnum primers, like a CCI #450. If you need some, let me know, I have 200K plus of #400 and #450 primers.