Hey guys,
Have a Winchester 670 in .243 with a shot out barrel (haven't actually tested how it shoots myself though)

So, suggestions on cartridges for it? Pretty sure they're also made in 30-06, was debating, if it would fit, maybe a 318 WR (I know, poor action choice but it's just what I've had for the last year and a half with no use for) or a 7x57?
Any other suggestions more than welcome.
Tis a pushfeed, not that that's entirely relevant for an Australia only use gun.

Cheers,
Troy.