mmpoeth,
I'm with JamesB on this one. Are you asking for effective range for shooting long range targets or for taking long range shots on game? The two questions will get different answers. If I'm just shooting long range targets, I don't care how much energy the cartridge has when it arrives. Additionally it doesn't matter if I'm a little off on a paper target. When it comes to game, I want at least 1000ftlbs of energy left when it arrives, and I'm one heck of a lot more concerned about "threading the needle" and not wounding an animal. Please specify and we can answer your question much more effectively. By the way, the 338 Win is a fine cartridge.