H&N 177 baracuda hunter and 13gr slug BC

Shot a few of the 10.49 gr h&n barracuda hunter and their 13gr slugs over the labradar last night. Since I had the info I was curious for about the BC. Shot through a dreamline
Low setting
10.49 Baracuda hunter, v0 = 645 fps, v20 = 596 fps, BC = 0.023
Med/high setting
10.49 Baracuda hunter, v0 = 943 fps, v20 = 846 fps, BC = 0.023
13gr h&n slug, v0 = 871 fps, v20 = 835, BC = 0.0593

The baracuda hunter matched the printed BC. The printed BC was 0.08 for their slugs, mine was lower, at least at my speeds. But speedwise, the slugs were shooting at am extreme spread of 3fps!
 
Was able to do some testing with the labradar again, testing some pellets for accuracy for an upcoming silhoutte match. Is the 8.44 exact usually that much lower on BC compared to the 7.87? This time I was able to get the labradar to pick up at 30 yards for my max distance. BC was calculated using airguns.net and the AoA BC Calculator, usually they were within 3 decimal places. Also thought it was weird the 8.44 grain had higher velocity, but it did on both my lg300 and lg400, so I am guessing it has to do with the head size.

Air riflePelletGrainEnergyBCV0
LG400Exact7.875.40.024554
LG400Exact8.446.20.0176575
FX DLBaracuda Hunter10.4919.60.0224918.4
FX DLExact10.3419.50.0226923
FX DLExact Redesign13.4321.40.0264847.4
FX DLH&N Slug1321.60.054865.6