As others have said, the 1873 action is not very stout, but it is plenty strong for the 357 Mag. That said, you don't need to hotrod the 357 to kill deer or pigs with it. "The Gun That Won The West" in .44-40 (200 gr bullet at 1,200 fps) almost wiped out any species in the USA that people considered worth eating in the last quarter of the 19th Century, including antelope, whitetail deer, and black bears, so I imagine the 1873 can still do the job. Take it out and give it a go.
Never try to educate someone who resists knowledge at all costs.
But what do I know?