took my one deer this year with a SBR 300 8" barrel using Barnes TSX. the shot i took was under 40 yards and the doe ran about 50 yards before expiring.
i think next year that i will probably go back to a 16" 6.8 because it seems to be a more humane way to harvest. they rarely make it past 10 yards with that caliber.
the 300 sbr did its job at close range but i'm not 100% convinced that its the best setup.
I have seen deer run 50 yds with a perfect heart shot...so I wouldn't judge a gun/caliber based on that result.