I'm planning my next project rifle. I've just fired a CZ .416 Rigby and loved it.

I can access quite cheap Zastava 458WM or the longer actioned 375H&H Rifles. (ie: Remington 798). I use Lothar Walther pre-chambered barrels and have a Richards Microfit Brown on Brown Laminated stock to suit.

I will be hunting Buff and larger plains game. Which calibre and action should I choose ?