I think the gentleman from Texas was saying there isn't much difference in trajectory between the LR and regular Accubonds, but the difference in BC, and by extension trajectory, is only part of the "long range" design of the bullet.
I'm not sure what you are asking, but instead of needing an impact velocity of 1800+ fps to get expansion like the regular Accubond, the Long Range Accubond needs only 1300 fps according to Nosler.
Edit to add:
Consider this - start the 129 gr LR AB at 2200 fps out of a 16" 6.5 Grendel (or similar capacity cartridge) and still have a 600 yd range (as long as you can dope the wind and place the shot accurately). Or more realistically, with a MV=2200 fps have 1600+ fps impact velocity at 400 yds (enough to expand the LR AB) with 10 mph crosswind drift of only 15". 1600 fps is below the regular Accubond's minimum impact velocity, but well above the min. impact vel. of the LR AB.
I don't know if the 129 gr LR AB would work in a 6.5 Grendel, but it would be an intriguing possibility.
