I've never shot a Cape buffalo or an elephant, so I can't comment on any personal exploits of that nature.
But in killing a significant number of black bear, there has been in my experience an unequivocal distinction in effect between .458-cal (.45-70 and .458 WM) and .358/.366 calibers. With non-CNS hits, .458s put them on the ground where standing, not to get up again -- mostly dead before hitting the ground. The mediums killed them within 20-25 yards with good hits to heart/lungs, but did not stop them.
I go prepared for the possible worst case scenario, not the best.
If a person can't shoot a .45-70 accurately, that's not the fault of the cartridge. The same hold's true for anything else over .40-cal. I'm closer to 82 than 81 and just a couple of days ago came across a full box of 500gr Speer Grand Slam Africans. They'd been sitting on the dealers shelf "forever" at $89.99 + tax. I got them for $52.99 + tax. Do I need them? Well, yeah, kinda... you see I have this thing for .458" bullets. They'll get shot at the range at 1900 to 2000 fps, with a couple at 2200. And a couple more will be reserved for a bear. I can't wait!
And, oh... I have arthritis in my hands, diabetes and one eye. I must be the one-eyed giant, right? Well, I'm actually (now) 5' - 8" (bare feet) and 165 - 170 lbs most of the time.
You see why I don't have a lot of patience with guides, outfitters and PHs who make excuses for "hunters" poor shooting while accepting them as clients. In parts of Africa the laws mandate the limits of what one must use for certain large and/or dangerous game. In those cases, the client must use a .375 or larger. He/she doesn't have an option; they MUST practice to become competent shooters, or agree that the guide/PH, etc. will finish the job if they foul-up! Why then, do "they" complain if they need to learn to shoot something larger than small to medium bores? Sorry, but I don't buy the excuses.
If I could learn to shoot a .458 Win Mag with full power loads in my sixties (three 500s into moa consistently), I see the only possible reason why another cannot legitimately do the same would be due to some physical infirmity (or mental blockage that can be overcome with training and practice).
