1. 
   Mg3
   The MG3 is a German general purpose machine-gun being the earlier MG42 (MG1 or MG2) further redesigned during 1968 to accept either the German belt or NATO disintegrating link belt, and later a 150 round belt drum magazine.
   Found op http://www.probertencyclopaedia.com/browse/FMM.HTM
   
   
2. 
   MG3
   (from the article `MG42`) ...German army after its modification in calibre; guns that had been reworked from the old to the new calibre were then called MG2, and a further ...
   Found op http://www.britannica.com/eb/a-z/m/83
   
   

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