223 3 gun long range load?

[Clay1]

I will be pulling the trigger on the Hornady 55 FMJBT for 250 yards and in but need something for 300 to 600 yards. Should I just go to the 77 grain pills and skip the 69s. What is a good projectile that will get the job done without being $300 / 1000.
The two rifles that I shoot: 1 in 7 and 1 in 8 for twist rates.
Considering the new Sierra TMK or Berger but the pricing on the Nose CC seems much better.

[Clusterfrack]

I'd go with 77gr. Here's my load:
77 gr Berger OTM
24 gr IMR 8208 XBR
Length: 2.264-2.265 in
Primer: CCI #450 (SR Mag) (= CCI#41)
Velocity: 2782 fps (18” barrel)

[Lon]

I just bought factory Hornady 75gr BTHP match when I needed long range accuracy (at Ft Benning 3G) but I think we only shot out to 450. I never left one of those plates behind without hitting it. I was using a 1/8 Rock River stainless 16" Wylde chambered barrel. If I needed extra shots it was my fault not the loads or rifle.

[SLG]

I just bought factory Hornady 75gr BTHP match when I needed long range accuracy (at Ft Benning 3G) but I think we only shot out to 450. I never left one of those plates behind without hitting it. I was using a 1/8 Rock River stainless 16" Wylde chambered barrel. If I needed extra shots it was my fault not the loads or rifle.

I use the same bullet but loaded by Aysm. Very nice.