Dave,
I have more than a few rounds of Winchester Supreme ammo with 55-grain Ballistic Silvertips. The lot I have is superbly accurate in every .223 I've ever shot and I suspect it will be pretty decent in the 5.56 chamber.
I loaded a few mags with the ammo and it clears, so it will probably function fine.
Anyway that's my plan.
I'll probably throw a few boxes of assorted Black Hills and Hornady ammo in the truck, too.
Anyway, my project is kinda hanging-fire until:
a) our "guest" leaves
b) the best of all possible scope mounts arrives
c) I get stuff cleaned up at our church (I have a LOT of ministries)
d) I get my energy up and actually make the long trip to the range and spend the time.
Be assured, I WILL post just as soon as I get some data.
Blessings,
Steve