Has anyone heard of this round? Apparently uses the .460 Weatherby as a parent, necked to .510 and shortened to 2.5". Claimed ballistics are akin to standard .500 Nitro loadings. Is in Cartridges of the World 12th edition, page 213 in the wildcat section. Not wanting to have one made, just curious if anyone has or knows someone who uses one and how it goes? Any pictures for comparison of how it looks would also be much apreciated (I know, I know, there's a photo in the book).