From what I have read the 465 H&H pushes a 480gn bullet out at about 2370ft/s I think, and I'm sure there are better performers on the market but I've had a sweet spot for the 375 H&H for a long time so when looking to build something more serious I couldn't go past the 465.

and what a beautiful classic looking cartridge it is too, with its long tapered sholder, just like a big 375.

Thanks for all the replies.

I also found that Krieger make a 465 barrel in 1-18 twist