So, just out of curiosity and bored while drinking my coffee, I did the math with M33 ball ammo for the 50 BMG, which produces 12,400 foot pounds of energy according to a quick google search.
Buffalo Bore 500 Auto Max produces 2,770, so it would take 4 and 1/2 shots to equal the BMG
M855 produces 1,325 which would require 9 and 1/3 shots.
M80 produces 2,559 which would require just under 5 shots.
CCI Mini Mag produces 127 foot pounds, which means you would need to shoot the target roughly 97 times haha.