At 300+ yards, the '06 has more energy.....you lose 2 inches or so in drop.
Maybe with your very mild handloads,but not if both cartridges are loaded to design pressures with the same style of bullet and optimum powders for the cartridge.
the '06 is a superior Elk/Moose rifle.
In your opinion.An opinion that many other people including myself would disagree with after seeing many elk and moose killed with both cartridges.