My experience of elephant hunting in Botswana between 1996 and 2014 was that my .500 was incredible as a back up in close quarters but as more and more elephant hunters opted for brain shots in thick bush , I had more runners and from 50 yards and going the .500 was not efficient , whereas my change to the .500x .416 Krighoff changed the game and the runners could be dropped at anything up to 100 yards. My service rifle in the Parks was a .458 model 70 Winchester , as were many of the Park rangers in the 1980's. I was 100% confident in the thick bush of the black rhino invested bush of the Umfolozi Game Reserve while carrying the.458 having many an encounter with lion and black rhino.

I for one, TRUST what Graeme says !!!!!

But Mr C , yours was coming at us with intent and fell 13 paces from where we were standing , unforgettable and within 1 hour of the hunting season opening . A bull of a lifetime and the way the bull went down with its front legs under him and rear legs spread back is etched in memory .

Size does matter, both in elephant hunting and in sex. (Its just that most men don't want to admit it.)

BH63

I do not have the truly large game experience but lots of deer, one elk, more than a few feral pigs, and one big euro boar proved to me the cns shot, and even with deer bigger is better. My Pa told me once that if you can tell a difference just looking at it, then something can tell the difference being hit with it.
Made since to me then and still does.
I saw a guy illegal shoot a deer through the top of the skull with a 22 lr. The deer literally stumbled around for five yards. You could not see the entrance whole for the hair covering it. He did not shoot it twice. I was a child and did not have a firearm to speed it up.

Guys...you know what I never hear about in these threads...Sectional Density as a measure of true knockdown power.
I have read and I believe that Sectional Density of a bullet/caliber/velocity is the only real mathematical measure that makes sense.
Most of this other stuff is pure anecdotal rhetoric mostly.
Anyone here believe or not believe in Sectional Density as the best real measure?

SD given equal bullet construction and velocity and assuming that the rifle twist can stabilize the bullet means more penetration. Without penetration caliber and expansion is meaningless. So it's real important.

Guess it depends on what information you find more credible. For me, I will take the anecdotal observations of folks with a huge amount of actual field experience, like Taylor, Thomson, Harland and others over the theoretical predictions resulting from mathematical formulas like sectional density. While both have their place, I certainly attach more credence to the former.

Agree with both of you.
i think you must assume the other variables with bullet construction etc is equal.

And, given the minor differences that occur in certain large bore calibers there must be something else that can't quite be measured and understood other than practical experience across a large number (exactly like with the guys you mention Mike)
My next gun I believe is the .458Lott As a result and then maybe a .500+

I believe Taylor preached sectional density. I believe the evidence has turned that better bullet construction (material and nose deign) at least in solids is more important than raw S.D. But today you can have it all: S.D., caliber, construction,rifle, velocity, and energy. Even our scopes are 1x to 10x in manification now. I believe that it is not one variable, but a combination and balance of all. What the big bore guys said was that as the game got larger the traditional big bored gave the best balance of all variables. Choose your side, practice, and good hunting. The 375 class for all is applying velocity, range, bullet construction, and S.D.
If I could only have one rifle the it would be a scoped 375. I have three and use them for everything I can get a tag for. But when people who have road the river tell me there are better tools for some jobs, I believe them. Especially, when it tracks with my personal observation. I would rather have a 570 510 caliber at solid velocity then a 350 grain 375 at similar velocity. I would rather have the 375 then a 1400 fps 50 caliber given anything near appropriate bullet design for game discussed.