I do not understand the obsession with attributing British guns to being made of Belgian parts . Yes there were some barreled actions brought in from Belgium . Yes Belgian barrel tubes were imported in large quantity due to cost and the fact that the Belgians were still producing damascus up until 1939 .
As to the rest, men in Birmingham were as capable of producing crap as any continental and indeed did so . Other than the tubes which could or could not be Belgian I see no hint of any component of this gun that is not English .
Wild fowl guns of the period were not as rule other than basic quality and functional ,this seems better than a lot I have seen the fact that it has survived this long is its own testament .