Buffalo hunt this past April where I had to borrow a gun due to mine being stolen in Qatar, I used Michael Mendes' 454 Casull. He had loads that were mainly a hot 45 Long Colt, nowhere near a max 454 load. The first shot dropped the buffalo to his knees. He staggered up and the second shot put him down for good. With a hot 45 Long Colt and 300 grain bullet. And this is a big Cape Buffalo that a lot of gun writers will tell you you have to have a 375 H&H or 458 Win mag to put them down. I have pics of John Taffin taking big animals, Bison size, with a revolver that some "experts" will tell you is only good for deer. But shot placement is the most important thing. If you don't plan on a hunt for the big bears then your 44 Mag will do everything you need. If you ever get a chance to buy Al Goerg's book Pioneering Handgun Hunting, grab it. He shot just about every thing there is to hunt with his S&W model 29 in 44 Mag, including Brown Bear. And the model 29 won't handle the extremely hot loads. So he was using loads that these days we would call hot 44 Special loads. I think Al shot everything with lighter weight hard cast bullets with gas checks and some half jacket bullets. Hang on to your 44 mag and work on shot placement and you will be set for anything in the lower 48.