@backyardsniper I went through the same thing as you. I built a .260 AI, it is the best all around. Get a 7 or 7.5 twist and load the 156 Berger for hunting, 153 a-tip or 150 sierra for targets. In my 29" I'm getting 2940 fps with the 156, well below max loading 2.950" OAL in my AICS mag. Stupid accurate. They are jumping .060" in a SAAMI throat with 1400 rounds down it, but don't seem to care about jump. I also talked with a guy that is sending the 156 @2725 fps from a 20" barrel as well, so that gives you an idea.
The only way I would look at anything else is if I was excluseively hunting elk, and even then maybe not. The only other consideration for hunting big game would be a 215 in a .308 or .308 AI. Loaded to fit in an AICS type mag is going to get you 2500-2600ish with a 26" tube. If you throat a .308 and load them at 3.100" or so, with 28" tubes you can get 2650-2700 at max with the right powder, pretty insane. In a 24 savage I have loaded up to 2580, best accuracy was 2525, seated to fit in an AICS mag using RL17. Wind drift isn't bad, about like factory loaded 6.5 creed performance but WAY more energy, but also with a trajectory arc like a rainbow. Better be nutz on with your range.
For any and all high bc bullet considerations, a 6.5x55 and anythingx284 is a long action only application. And also, you don't really gain anything with those over a .260 AI other than they won't fit in a short action, and you don't have to form brass.
If you want any more info on the .260 AI, from brass to powders to primers, p.m. me, I have done a lot of loading with mine.