I'll throw my $0.02 worth on CFE223 using 55 grain Hornady bullets based on my personal results and loading for 3 other AR's with 16" barrels owned by friends.
Anything under max powder loads posted on the Hodgdon web site shot from poor to fair groups at 100 yards, indoor range, off a solid cement rest using a 30X scope with fine X-hairs. All rifles had excellent aftermarket triggers as well. Upon reaching a tad under to a tad over the maximum listed charge for the CFE223 powder, which is 27.4 grains, per Hodgdon, of CFE223 with a 55 grain bullet - groups really came together for all. My AR shoots excellent with a couple tenths over max, and will group right at or a tad under 1/2 inch - 5-shot groups. Outdoors the groups seem to open a bit but are usually under an inch - off hand at 100 yards outdoors the groups are usually within a small bushel basket.
I have a 2 moa Aimpoint mounted on my AR for everything except load development and anything the size of a prairie dog and larger are in Harm's Way up to 300 yards, that is, if I can see them, as if nothing else, I'll scare them. (I usually need a few "sighters"
on prairie dogs at 300 yards but 150 yards and closer that Aimpoint, 55 grain Hornady bullet in front of CFE223 will make the rancher very happy.
I haven't chronographed those loads but I'd hazard a guess the bullet is flying fairly close to 2,850fps??