Yes, you are correct. Range i shoot goes from 600 to 880 then to 1k. I load the hornady 168 and would have to load pressures somewhat high (and kept cartridge length mag length) to to get them to 880 while staying above transonic. So i just kept it to 600 and used other guns for beyond. I do remember my load would have worked well at 800, if thats where the range had a backstop at.
So yes you are correct. I just kept at 600 for so long, thats what i thought of it as out of habit.
Hmm, my M1A keeps 168 gr PPU supersonic at ~1180 fps out at 1000 yards. I would think a slightly shorter SCAR would still be supersonic at that distance.