With a 50 you can shoot a sabot/bullet combination that gives decent downrange ballistics. Some have pointed tips and decent BC. Blackhorn 209 gives good power.
I used a CVA Optima V2 stainless in 50 cal with the above set up to take a 25 inch mule deer at a bit over 250 yds in 2020. The scope I used has capability to dial yardage. The rifle and load combination shoots 1 inch groups at 100, and 3 inch groups at 250. That is as far as I actually shot the rifle on paper, but I have no doubt it would still group well at 300.
The Barnes 300 grain bullet I used hit the buck midribs onside, angled forward and exiting just behind the offside shoulder. (I wanted to break the offside shoulder but missed by a inch or so.) The bullet left a 2 inch exit hole in the offside hide, and similar sized holes in both lungs.
In short, that rifle and load combination would be capable to 300 yds, like everything else, if the bullet is properly placed. I did practice quite a bit before the hunt with this combo.
Manny
