Many Liege, Ferlach & St. Etienne tube makers produced Bernard pattern barrels, of which their were several, long after Leopold died in 1870
https://docs.google.com/document/d/1fMs-Mn60ei9QsRcHT5Urm_eHobzJnaDKZiP3FP0fXb0/edit

If the barrels were by his company, they would bear this mark