Yes, but any rifle for a 416 would need to be built far stronger than one that would max out for the pressures and lesser strain of a 9.3. So perhaps I am not being logical, and rather than rely on my limited gunsmithing skills (none) I called a friend of mine who is a Merkel employee of long standing. (They build both SXS and O/U.)

He said the reason one rarely finds a O/U larger than 375 (which they used to make but no longer) as there is little call for an O/U in the really heavy calibers. They are, according to him at least, used primarily for hunting in Europe and, from time to time, here in the US. The 9.3 is about as big as they go for these types of useage, and even the 375 was too much and has been taken out of their inventory. He said Merkel sales in O/U are mostly in the 9.3X74R and smaller calibers for the more traditional Continental and close quarter hunting in the US. He said that 'African' hunters prefer the SXS.

"Could we or any other competent company or gunsmith build an O/U strong enough to handle a big nitro caliber? Sure, up to a reasonable limit, but there is no market for one so you aren't going to see them."

I will defer to him on this, as this seems to make sense. Dave