While I love the traditional vintage British hunting cartridges, to the point of waiting on time to stock-up a .318 Westley Richards barreled action in my gunsafe (and waiting on affordable loading dies!), I have said many times that imho the .338 Win Mag is the cartridge the British gun-trade was trying to 'invent' all along!

.333 Jeffery, .33 BSA, even the .318 WR all fall in line behind the .338 Win Mag when it comes to ballistics and performance down-range.
Hell, the oft-criticized belt was even invented by the Brits!