From the well known custom revolver smith, John Linebaugh:
On the reaming, we don't feel it wise to chamber a cylinder to .475 that's .050" smaller in diameter than the standard Linebaugh built cylinder when dealing with the potential pressure the .475 Linebaugh is capable of producing. It's an uninsurable prospect. Can it be done? The answer is yes, but is it wise? No. Just discussing this I can assure you is sending shivers down the spine of Ruger & Co. as it is typed on open forum. They were very leery about releasing these for that reason. It wouldn't surprise me a bit to see the whole project shut down if much more of this talk about reaming them to .475 continues online. I know for fact they're spooked about it already.