The 143 ELDX changed significantly at some point. I swapped for an older box from a member here, but also had a sample pack from SubMoa (presumably newer ones). The bullet OAL was ~0.015" different, and neither was the same as what is shown above.
Older box = 1.445"
Sub MOA pack = 1.427"
Posted above = 1.382"
I know Hornady has changed bullets in their lineup before, and revised B.C.s here and there, but this seems a bit strange that there's at least 3 flavors, with 60 thousandths length difference...
FWIW, I calculated the G1/G7 B.C. for the 143X, using my LabRadar, and came out with an average G1 of 0.640 ± 0.01 and G7 of 0.313 ± 0.005. That's out of a 24", 1:8 twist, 5R in 264 Win Mag. Tracking files from 0-150 yds, so velocity range of ~3050 - 2850 fps give or take.