Bergers goals are narrower than Hornadys, they have performance benchmarks not related to BC and marketing, they can't make that benchmark with a tipped bullet, no one can as they just won't shoot as accurately. The on game performance has been a massive disappointment with the ELDX and ELDM, all most every guy I personally know, myself included won't run them again for game cause the lower BC Berger way out performed them. The ONLY thing that I like and kept me shooting so many ELD bullet is the price BUT in the end that's not worth it for how they perform. IMO
I concur. Going from 140 Bergers to the 147 eld-m, I was extremly underwhelmed in the 13 or so critters I killed with them. I know it wasn't designed as a hunting bullet, but I was hoping it would do better. When observing a couple ballistic gel tests, it essentially followed what I observed. Inconsistency. Even if the 156 has a lower bc than the 147, which according to berger and applied ballistics, it is better, I would still use the berger based on terminal performance.
If you already have a good load with the 140's, it may not be worth the time and load developement. I'll post a ballistics chart here of drop and drift with the 140 elite hunter, 147 eld-m, and the 156 projected bc at velocities from say my .260 AI (similar to a 6.5x284), a 6.5 cm, and a .264 wm, though the differences will be the same because velocity differences will be similar, you will see there isn't a huge gain in trajectory, and while it is a step up from the Berger 140, the trajectory difference isn't necessarily massive. Also there is a difference in energy, though again, not huge. In my .260 AI, 600 yard energy is 1756 ft. lbs with the 140 eh, and at projected velocity with the 156, is 1861 ft. lbs with the EOL.
So is it worth new load developement? That is for the individual to decide. If elk was a main target, the extra sectional density and energy wouldn't hurt. If I was building a new 6.5 hunting rig and I wanted to use Bergers, it would be built around the 156. That is the way I look at it.