Before 1914, only two companies were able to entirely manufacture weapons in workshops...in Leige..: the FN and tablissements Pieper.

Source: the remarkable work of Claude GAIER, Doctor of History and Director of the LIEGE ARMS Museum, Five centuries of Arms manufacturing in Lige, Editions du Perron, Alleur (Belgium)

With all the trade guns from Belgium it would be interesting to understand how many were from those 2 companies and how many produced in other 'states' of Belgium

Nothing is foolproof to a sufficiently talented fool.