Massive Spanish Naval Flintlock Blunderbuss Swivel Gun for comment

[Jim McDougall]

I am puzzled with the business on the RM marking, and Fernando K, very astute observation on the letters perhaps being PM with the 'P' later altered to an 'R'.
I don't have Stockel, and thus don't have any entries for Paul Meitinger, an Innsbruck armorer.
However I do have references to PM, Peter Munich as well as Friedrich, both were Solingen swordsmiths working in the 17th century, and seemingly part of a family by this name. However Peter often signed 'Munch'. His mark (mid 17th) was a bishops head flanked by initials PM .

While armorers and of course swordsmiths often did also work as gunmakers. I have never heard of the 'Munich's' being other than swordsmiths.

If Peter indeed marked the lock of a gun, why would it have a crown? and why would the 'P' be fashioned into a 'R'.

Also, I have always thought of the circular fixture on the lock denoting a Spanish lock ('miguelet'?) so why would a Spanish lock be made in Solingen?

I do not mean to discount the theory, but honestly do wonder on these matters.