This is a topic that has me going in circles more often than not. As a lefty I am always on the lookout for good rifles to build up my ideal battery. I have set a limit of around 5 rifles as I would want to know them like the back of my hand. There are so many variables to consider.
Initially I gave thought to building a do it all battery based on regular increasing bullet weight: 50gn (.22), 150gn (6.5mm/7mm/.30), 250 (9.3), and then a big bore +400gn.
As it stands my battery (4 in the UK, 1 in South Africa) is as follows:
.22lr CZ 452
.243 Ruger No.1
.308 Ruger M77 Hawkeye (South Africa)
.30-06 Winchester M70 Classic stainless and walnut
.375 CZ 550 Safari Magnum.
My current thinking is to rebarrel the Winchester to 280 and add a synthetic stock and longer range scope (i.e. foul weather hunting and range days).
Most of my hunting is done in Africa, but I would like to start hunting here (I have a DSC1) and also in Europe.
Any input would be most welcome.
This really isn't that bad as an all round battery
Got a .22lr because you always should.
.243 Ruger number 1 - Would you change this for another bolt action? Some of the 6mms do quite well for the longer range target stuff (Proper twist rate barrel)
.308 Hawkeye - as it is in South Africa you arugably have space for a UK slot between your .243W and you could argue for a 6.5 or 7mm to fill that space, especially if it was a Long range target type rig* (More below)
.30-'06 Winchester - you can literally hunt anything in world with this that doesn't get into DG territory. I would leave it alone
.375 CZ550 Safari Magnum - again, really versatile chambering. Wouldn't mess around with it.
You do need a nice little .222 or .223 Rem. I'd go for a CZ527 .223 Rem in the American or Varmint but there are lots of choices out there.
Now, your 6.5/7mm longer range target build - I went through this thought process for my longer range hunting / Bisley build. Have a look at "Beanfield Rifles" as an idea for a compromise.
Chamberings I would consider
6.5 Creedmore - if you really must...
6.5x55 - The Swede gives you lots of options in factory and performs similarly to Creedmore. Also more Mauser type rifles in the 6.5x55
6.5 PRC - Looks interesting but a real hand loaders proposition (Weatherby and 264 Win Mags not easy to feed even if you hand load and barrel burners)
In the 7mms
7mm Rem mag is well known, Lots of ammo choice and load data but needs a magnum bolt face action and is belted which bothers some people for reloading.
280 Rem (or AI) looks an interesting proposition but in Europe really a hand load only option (the French seem to have a penchant for it, especially in auto-loaders though). The AI gives you 7mm Rem mag performance without the belt.
284W - Seems to have got some real interest among the "F-Class" Fraternity. Understand has a rebated rim though so some say difficult to feed but my experience of this is limited I'm afraid.
7x64 - This was my choice. Quite a bit of factory ammo in Europe. Also quite well thought of in sub-Saharan Africa. Usually has a longer throat and 1:~8.7 twist so stabilises the long, heavy bullets for long range shooting (NB - 280 Rem and 7x64 are virtually the ballistic twins of each other so if you want that kind of ballistics, pick the one which floats your boat)
You can get other faster 7mms like the 7mm Weatherby and 28 Nosler but these look like real powder and barrel burning monsters.
A word on twist rates: get one which will comfortably work with the bullets you want to shoot.
And whatever you choose, enjoy your shooting.
Scrummy