Here are velocities I got for factory Hornady 123 grain SST at 70 degrees using a Magnettospeed chronograph with AR-15s. Just for reference a Friend used his 24 6.5 Grendel AR-15 to take a buck antelope at 500+ yards at 7200 ASL in Wyoming. My Friend was using a Max load of A-2520 with a 120 grain Nosler hunting Ballistic Tip. He had used this load to take numerous antelope, some with his 18 6.5 Grendel and some with his 24 AA 6.5 Grendel.
123 Grain SST Hornady
12 2277 (chrono by forum member with lab radar)
16" 2430
18" 2493
20" 2511
24" 2583
Just for comparison here is a hand load using 31.0 grains CFE 223 and 123 grain Nosler CC I chronographed on the same day. LeveRevolution will give very similar velocities to CFE223. I got basically the same velocities using 123 grain A-Max as Nosler CC.
Hand Load 123 Grain Nosler CC, 31.0 grains CFE223, CCI 450
16" 2449
18" 2471
20" 2526
24" 2619
123 Grain SST Hornady
12 2277 (chrono by forum member with lab radar)
16" 2430
18" 2493
20" 2511
24" 2583
Just for comparison here is a hand load using 31.0 grains CFE 223 and 123 grain Nosler CC I chronographed on the same day. LeveRevolution will give very similar velocities to CFE223. I got basically the same velocities using 123 grain A-Max as Nosler CC.
Hand Load 123 Grain Nosler CC, 31.0 grains CFE223, CCI 450
16" 2449
18" 2471
20" 2526
24" 2619