The problem most people have with Barnes is they do not seem to expand as well as lead core bullets when the velocities start to dip.
I love Barnes X bullets, and I use them in several calibers; however, they do need, imho, to be fired at 'magnum' velocities and more reasonable ranges. I am shooting 140 Barnes X in my 300 SAUM this season. It shoots the best and shoots flatter than my 150 ABs, but out past 350 yards or so, the AB have performed much better in expansion tests.
I know the shortcomings of expansion tests compared with live animals; however, this is a means to get an idea or a peek to the bullet's tendancies at these ranges. If I had a camera I would show you the proof.
My personal limit is to keep impact velocities over 2400 fps or so. That seems to be the bare minimum I have seen to get the expansion I require of the bullets. I have taken game with Barnes X with impact velocites of 3400 fps, and the performed flawlessly. I recovered one from my 25-06. I use 75 gr X loaded to 3550 fps. I shot a mature buck at about 45 yards. The retained weight is 74.8 gr. For comparison, 100 gr NP fired at 3400 fps, impact velocity of about 3340, bullet weighed 40 gr. Both bullets broke both front shoulders, dropping the buck, but the deer shot with the Barnes had less meat dmg.
The Barnes will kill just the same as lead bullets, but typically, lead core bullets give better/bigger exit wounds for trailing game. The Barnes do massive dmg to the vitals, they just don't seem to make big exit holes, but they do tend to always make an exit hole.