So you know the skinny from every other person who has been to Africa about your choice of Rifle. Everyone has advice on this matter, even if they haven't been there.

To travel with a gun is becoming more complicated each day and I foresee a day when all hunters would rather use the rifles provided by their PH or outfitter.

BUT there is nothing like hunting with your own rifle and an essential to any trip is hunting with a rifle that you are used to rather than going out and getting a bazooka just because its Africa!

If you're hunting the big boys then the classic double is the dream. Whether you can afford this is another story but seeing a buffalo bull take 500 grains twice in a matter of seconds is a memory not ever forgotten.
Unless you're a plinker there is no need to go out and buy a new rifle specifically for African game, a heavier caliber deer rifle works well on most plains game and some even do for the cats.

It is when you start messing with elephant, rhino and buffalo that you need a true weapon, a big stick so to speak.

Here's what I think on the subject of rifles for Africa:

Heavy thick skinned game - Elephant, Rhino & Buffalo
You probably wish you had a dollar for every time you heard this, the .375 Magnum is the caliber for the big boys. Well...... that is partly true, in most countries it is the minimum you need to be able to book a dangerous game hunt, but nowadays there are such mouth watering guns for the big boys that a .375 magnum is a bit of a let down.

Don't mistake my banter, the .375 Mag will do the job each an every day for 100 years. 20 years ago in Africa, this was one of the biggest calibers you could get. So don't discard the faithfull old workhorse, it is capable of handling everything Africa has to throw at it and is on the very reasonable end of your budget.

BUT somehow the bigger calibers feel better, their barrels are thicker and you know immediately, when you lift the rifle to your shoulder that this is a tool for a serious job. I'm not talking about the expensive doubles, I'm talking about rifles that will cost you a little more than usual but they are built for the purpose of close range heavy work and will throw out 500 grains of hot lead with enough knock down power to make you safe.

I GOTTA LOTT
In my opinion, the .458 LOTT is the perfect rifle for the big game of Africa because of its size, the knock down power it delivers and because of its availability. Winchester did make it in factory version yet your best bet is to buy a regular .458 Mag, used is cheaper, and get it reamed out by a competent gunsmith into the LOTT version (believe me, you don't want an original .458 Mag, it does not work well). Without a doubt, the LOTT carries serious hitting power and is the choice of many PH's across Africa. If you cannot afford a double, then this is the best choice.
Of course, here I am touting a rifle that I don't even use, because of one primary reason: the rifle I have fits me, it knows me, I know how it behaves and it works for me. Believe me, I own a .458 LOTT and have used it and know its capabilities, that is why I endorse it.

THE OLD NITRO
The .416 Rigby was one of the first large game nitro calibers and to this day it is a very good all rounder. This is what I use and personally I would prefer a 500 grain bullet because the Rigby to me is akin to the .300 Win or Weatherby Mag., it is fast, it penetrates and it kicks the shit out of you. 500 grains might slow it a little and make it more manageable, but it is another top choice for your big game hunt and you can use it on lesser game at a greater distance. It is well suited for Moose, Elk and of course the American bigwigs, those magnificent brown bears of Kodiak.
You have the Americanized version of this, the .416 Remington. For what it is worth, when you look at the cartridges side by side there is little difference but in the field they are 2 different calibers, something I have yet to fathom. Seriously, as a PH who hunts mostly buffalo each year and sees many calibers, I notice a difference, there seems to be a lack of power or perhaps it is just that people are afraid of it! This caliber evokes caution in me whenever I have a client shooting it. Most of the time it works out perfect though!

DOUBLE DREAMS
They're too heavy for me but for the purpose of hunting the dangerous game of Africa, they are second to none. Old gnarly PH's pull them out at every opportunity and ask if you want to buy the stick that killed 500 elephant! Today they are cheaper and they work well yet most still throw a 500 grain piece of lead so your only advantage is a second shot, which probably turns out to be too close or even worse, you pull both barrels at once. The .470 Nitro is the most common, the cheapest and still only gives you 500 grains? BUT you get the image and they make some immaculate guns. Ammunition is also factory produced so, like the .458 LOTT you can make it more economical on your whole pocketbook. If you do buy a double PLEASE make sure it is from a reputable manufacturer and dealer - double nightmares do happen, even with the top brands and manufacturers.