You can get anything you desire. As for Africa, and Plains Game, anything from a .270 on up should do the job. Of course, bigger is better. Were it me, I would get a .338 Win Mag., and use it for everything. If you need a bigger gun to hunt the big stuff, the PH will be able to either get you a loaner, a rental, or let you use his. In any case, a .338 is more than enough for everything else. Keep in mind however, some countries have a .375 minimum caliber for certain types of game.
Hope this helps

Find yourself a rifle and cartridge to hunt deer with. In a couple years when you think you might go to Africa, you'll discover that the cost of a new rifle just for Africa will be pocket change. If you spend time researching cartridges and rifles for Africa for a couple years, you'll be well ahaed of the game.

Maybe Kevin Davis or Duggaboy will drop in.

When went to South Africa in 2005, I rebarreled my .30-06 Savage 110 into a .338 Win Mag. It did did every that was needed and the brass, bullets, etc are still relatively inexpensive compared to the bigger and more exotic cartridges. When I returned, I put the .30-06 barrel back on for deer season.

That said, I would suggest a rifle that can be easily rebarreled by you rather than by a gunsmith since will keep cost down and allow you to go with different chamberings in case you get interested in something else. So either a Savage 110 or a Thompson/Center is what I would consider. The T/C can be rebarreled easier and faster with few if any tools but the Savage has the advantage of a magazine if that is important to you.

Whatever you decide on, if you want to use a scope be sure to get one that is rugged and has plenty of eye relief!

did you change your bolt face also?

if this is the "type/style" rifle you are looking to get into, go with a .308.

with a 19" bbl, your not going to get full velocity from an 06. for an 06, i would not go shorter than a 22" bbl

Yes. I already had a magnum bolt face from a 7mm Remington Magnum so I didn't have to buy one. You can buy them completely assembled from Sharp Shooter Supply which is where I bought my barrel nut wrench and machined recoil lug. The recoil lug wasn't really needed but I figured I would replace it with a better one while I had the barrel off.

I agree with Don about giving yourself some time to research, but I'll give you my 2 pence anyhow. The 30-06 would certainly work for what you are wanting to hunt in Africa. That said, there are definitely several different cals that won't kick too much that would perform better on African PG. African game are notorious for being tougher than N. American game.

I think your best bet in terms of performance, cost, and ammo availability will be the 338 win mag. It can shoot 200-300 grained bullets, and it's flatter shooting than the -06. I would recommend something that can shoot heavier, better penetrating bullets. To me, heavier is better than faster in most cases, particularly on hardier African game such as zebra and wildabeast. Ultimately, the most important thing is placement and bullet quality.

Another suggestion would be the 375 H&H or the new 375 Ruger. Recoil is really not bad at all in a reasonably heavy rifle, and you've got enough power so that you'll potentially be prepared to hunt some DG if you so decide. The 375 is perhaps one of the more versatile cals available. My 5'3" wife has shot my M70 375 off the bench without any trouble.

Some other suggestions you should look into;

35 Whelen, 338-06, 338 federal, 9.3x62, 8mm remington mag, 350 remington mag, 7mm-08, 7x57, any of the 300's although they aren't my favorites.

Good luck, and let us know what you decide.