Not defending the way applied ballistics has behaved themselves in any way, honestly I haven't payed any attention to it or seen it, likely I just wasnt looking at the proper threads to see it. But when you run numbers, have you actually seen how little difference there is in impacts from what hornady says vs what applied ballistics says for bc's? In reality, if we are running anything less than top tier optics, or unless our chronograph systems have ZERO error, or if we adjust our velocity to match our impacts ANY, then the error could be in our equipment, not the hornady vs applied ballistics B.C. . And even then, small up or down drafts in the air or other environmentals could also make it different and match/not match our come ups from our calculators. If you run the applied ballistic custom drag curve for the 147 (roughly .315 G7), and compare it with the average of the 3 different bc's listed on hornady's site for the bullet at different velocities (.334 G7, this is what AB does when they list a g7 bc), and again compare that with the mach 2.25 bc, the highest velocity B.C. that hornady lists (.351 G7), out to 1000 yards, the difference is so minimal that it is somewhat comical it's even being argued over. From the .351 G7 to the AB custom drag curve, there is a difference of 6.3" of drop and 3.91" of wind drift in a 10 mph wind at 1000 yards. When you average the velocity range of the 3 bc's that hornady lists, as AB does with their listed G7 bc's, the difference is now 2.7" of drop and 1.68" of 10 mph drift, again, at 1000 yards.
Let me put it a different way, if you increase the velocity of the AB load with a .315 bc by 16 fps, it matches exactly the numbers of the .334 bc at 1000 yards. If you increase it by 39 fps, it matches exactly the numbers of the .351 bc at 1000 yards. The majority of us shoot loads that have an e.s. in the teens to low twenties.....if the center of your 4.5" 3 shot group at 1000 yards tends to be an inch and a half to two inches low/high of POA, how are you going to know if it's the AB b.c. vs hornady b.c., your drop calculator, air temp or wind differences, a tail or head wind, paralax, mirage, your shooting abilities, your optics tracking abilities, a hot barrel, your own loaded ammunition, the way you supported the rifle for your shots.......This is a deep rabbit hole people. Or are you just going to add or subtract 10 fps to your calculator, or add or subtract 1 click at extended ranges, of hold roughly an inch higher or lower at 1000 yards?
As stated, I feel we often put too much into the numbers that manufacturers print on a box. A .315 bc vs .350 bc means literally inches at 1000 yards, which very few of us kill game at that range. Look at your average distance you take game at, mine happens to be slightly over 600 yards, and see really how much difference there is in bc numbers. Applied Ballistics, Hornady, it doesnt matter to me. They both provide a tool that I use to put lead in meat at extended ranges, and they both work. With either one, we need to validate our drops to ensure we make good hits. Many times that includes making minor adjustments. And right there, any argument between the two is somewhat invalid. If either were perfect, we would never validate drops.
Just stuff to think about.