The grade of inspector on the previous and later systems was designated by 1 and 2.
With only one example it can only be a theory.
Not many guns were produced immediately after World War 2, there being strict controls on supplies of raw materials. This gun could have been one started Pre-war and left unfinished until things calmed down.
I am hoping that of our members might have, or remembers seeing , a similar stamp (M 947 or M 949) accompanied by a lack of the usual date stamp. That would be fairly conclusive.
