Nframe,

I have the CZ 550 American Safari in .458 Lott too. Nice rifle. Per your question about ammo, I found mine (Hornady 500 grain soft points) through a local Bass Pro which uses a source known as www.zanders.com. This site is mainly set up for FFL holders and dealers but, customers can "look" at the products too. Might give it a try.

A question for you - did your rifle come with cross bolts? Mine has none (at least that I can see) and I'm worried about the stock eventually cracking.

-Vlad