the 450 NE with its original ballistic is good for anything but you dont need so much also for the biggest north american game. the 45-120 have a maximum CIP pressure of 2200 bar.

here you have pressure testet loads for this cartridge

all under 2200 bar max, under CIP, the proof house mellrichstadt have a test barrel

a 485 grains lead bullet makes 555 m/sec / 1820 f/sec giving an energy of 3577 ft lbf /4851 joule

to compare

405 Win 3,236 ft lbf /4,387 J

9,3x74R 3,434 ft lbf / 4,656 J

450 NE 4,930 ft lbf / 6,680 J

I would say this is just rigth for the biggest american game grizzly, polar bear, buffalo, moose

a lot of power but no overkill

sure, you can build a 45/70 but when I have to make the work it must be something extraordinary,

70/150 here with .577 snider to compare

interesting big bore