Not incouraging anyone to violate the minimum caliber (if one exist) when it comes to to size but a 6.5x55 in the correct location with a suitable bullet beats a .500 NE in the wrong location any day of the week. Also Big Bore would depend on whether you define it as starting at .400 or .450.
jp, i would ask what you consider a "large bore" we in america tend to go on the light side of large. here a 375 is a "cannon!" in africa, i believe it is considered a medium. so, the 450-400 is pretty mild. the 416's or 404 jeff can be loaded down to whatever you consider a reasonable price to pay in recoil. above that level, you are out of the "MILD" category
