I'm interested in purchasing a rifle that would be considered for "big game and long range" hunting in a semi-automatic.
You need to more fully define what your intended game is to deterrmine what kind of impact energy you require.
Then you need to define what you consider long range to determine what kind of accuracy you'll require.
ummm are those all yours? if so I think you might be a long lost brother of mine lets meet at your place and discuss over rifles.I think there is one and only one question that needs to be asked that will determine "THE" gun for your needs/wants!
How much are you willing to, or can you spend?
Money means everything and size matters in dollars and caliber!
Actually some states like Pennsylvania don't permit even your BAR because they don't allow any semi-auto guns.I have a pair of Browning BAR rifles, semi auto sporting rifles with real wood and blued metal.
...
Large capacity mags are useless.