Just curious.

I made up a couple. Looked like an apple in a sock. Could be done and you would likely see 20 fps gain over the .458 bullet

The 470 Accrel is the same length but capacity of the Capstick and then some

I made up a dummy years ago, not sure if I still have it.

The reason I could see for making such a round is if you cast bullets for the .475 linebaugh or 480 ruger and hence have a nice collection of 400-440 gr bullet molds. It would be an outstanding platform for launching those bullets at the cast bullets sweet spot of 1800-2200 fps.

Asside from that specific use, I have a hard time getting excited about such a round. I think the 2.5" belted case looses usefullness when you exceed 40 caliber. The 458 win mag should have been the 458 watts from the get go, and I can't see going to the expense of making a custom in .475" and not using a case with at least the capacity of the 470 capstick.

That extra bit of powder capacity makes for a much more flexible round, and big bores call for big actions. Any action suitable for a 2.5" case will take the 2.85" case.

I agree, the 458 case is short on powder space and big on compaction as is, some of that would be oleaveated with a 475 hole in it, but not my enough to make any difference..The Capstick would be pretty hard to beat IMO as it fits the same action, has enough powder space to make things work, and would probably hold more down than say a 475 on a 404 case for instance..An extra round makes up for a lot in a DGR IMO. You seldom need it but when you do its just real handy.