There seem to be several recent production DRs in 416, Merkel, Kreighoff, etc. I do not see the 416 listed on the current US importer sight. I suppose there is no reason that, given modern steel and construction, the 416 would not work. Indeed, there are a fair number of late 1950-1970s DR in 458 Winchester, another higher-than-Nitro rounds.

If you want, I'd give Danny Span down at Merkel USA a call. He is sales, but a DR enthusiast and has always had an honest answer on Merkel questions when I call. Dave