My apologies gentlemen I should have been more precise in my comment, by bad!
What I meant by: "All I will say is that there is no way on earth "Black Death" is walking away from a heart shot with a 300 Win Mag, period!"
Is that the animal would NOT SURVIVE the shot.
You are correct! Any of the .300 Magnums with a premium bullet placed in/through the heart will mean curtains for Mbogo. Many have been dispatched by .303 Enfield and 7 x 57 in colonial days, but I don't recommend it!