Always an interesting topic and, as others have mentioned, no definitive answer.

As with many of you I've been playing with lots of various cartridges in as many different rifles, domestic, British and German, for quite a few decades in both smokeless and black powder guise. The one thing that I have noticed more than anything else is the huge duplication in ballistics. There is smokeless powder cartridges introduced in the last couple decades that do no more than some introduced prior to WWI. In my experience that holds especially true if one uses more modern, slower burning propellants. When one is using black powder cartridges the differences between American, British and German cartridges becomes even less. My 10.5 X 47R is essentially, ballistically the same as the 40-82 WCF.

When it comes to performance on game all I can speak to is experience gained in the lower 48. For many that will be pretty tame when compared to cape buffalo, elephant, etc. On game from the size of whitetail, wild boar and up to elk it seemed to me one killed as well as the next if the bullet is put in the proper place. As with most I prefer a bigger, heavier bullet for larger game but as the posted article mentions I too am a fan of the 6.5 X 54 M/S cartridge. Geez...how can one not like it especially when used in the svelte 1903 M/S carbine? Anyway, I doubt any game animal ever thought, "oh, he shot me with a 243 so that isn't as bad as being shot with a 300 Win. Mag." The deadliest rifle I have ever used, and I killed a boat load of game with it, is my Shiloh Sharps in 45-90 loaded with 80 grs. of black and a 480 gr. NEI bullet cast 25-1. There isn't a doubt in my mind any other cartridge sporting similar ballistics and bullet weight in any other rifle would be just as deadly. Is my 45-90 the best. Good grief no. I like it awfully well but I'm not that narrow minded.

The question of the necessity of Magnum cartridges always arises. I've owned more than a few rifles so chambered and if I were relegated to owning one rifle, God forbid, it would be a 300 Win Mag., provided I could still handload. There is others certainly just as accurate and powerful. However, I have a great deal of experience with that particular 30 cal. Magnum and besides, I just like it. Therein lies the only reason needed to own any cartridge. I don't believe that a Magnum cartridge in any caliber is necessary for my hunting or most others. If a person is willing to hunt harder, that is get closer to the game in question, and willing to set personal parameters those cartridges developed before 1910 are all that is necessary. But where is the fun in that? I used to live in Wyoming and prior to moving there had hunted the west quite a bit. I know all too well that there is sometimes no way to get closer to a game animal. Using some of the older, slower cartridges can perhaps prevent one taking a shot they might take if carrying a fast stepping Magnum. That's where setting personal parameters comes in, in addition to knowing ones abilities at longer range. Whatever my parameters are they certainly aren't for everyone. They're set because that's the way I want to hunt and are applicable to no one else.

I hear and read a lot about new, "premium" bullets. From what I hear and read their performance is exemplary. On soft skinned game almost as good as a well cast bullet...and I say that tongue in cheek. However, I don't see how they can possibly be any more effective than a well cast bullet of suitable caliber, weight and velocity when put in the proper place. I suppose one could call them the original "mono-metal" bullet. I must reiterate, using cast bullets is a choice I have made for me. My choice has no bearing on what others choose to use. It is certain neither is wrong.

For many who suffer from "magnumitis" I believe a previous poster described it quite succinctly. They neither have nor take the opportunity to become intimately familiar with their rifle and attempt to make up for ability with power. That is not much different from taking me who mostly drives a 1/2 ton pickup and sticking me in a Formula 1 Ferrari. I'm probably going to make a wreck of things.