1888 Commision Rifle

[Patrick Chadwick]

And definitely done in Europe.

On this point, I respectfully disagree. In countries that require proofing of firearms - which for the last century or more means probably every country in Europe with commercial arms production - rechambering invalidates proof and a new proof is mandatory. See Wirnsberger "The Standard Directory of Proof Marks". The land of unproofed wildcat conversions is quite clearly located somewhat further out to the West.