I should have been more clear in my original post. I have to use non-lead ammo for hunting because of my stupid State laws. My only other option are the Barnes hollow points which I have also, but don’t know how they perform on game.
The Barnes 300TSX is an excellent choice for the 45-70 and black bears. They are very accurate in my Marlin with H4198. I shoot them at 2,000 ft/sec but they can be shot faster if there was a reason to do so. I shot a 300lb bear with one and the bullet went through his shoulder and lodged in his spine. He flipped onto his back and couldn't move. He would have died in short order but I put another one into him to avoid any suffering.
Another option is Hornady's monoflex bullets, an all copper alternative. Lately I've been experimenting with them in the 45-70 and the 458SOCOM. In an 18.5" Marlin bbl, using their 250gr monofleex, I get 2,330 ft/sec with AA1680. I shot a nice buck with it last fall. The buck was hit broadside at just over 100yds. The buck ran about 35-40yds and fell over dead. The bullet had exited.
There are good options out there even for guys in the lead prohibited states.