writings on the edge of the cap top side in cyrilic are 'Art Teh Zavod Kragujevac' meaning 'Artillery Technical Institute Kragujevac'. M17/25 designates model of the bomb, 28/4 designates 1928 production year and 4 production series or LOT.
cross on cap is according to my findidngs added later as symbol for the weapon and amunition issued to chetnik batalions in serbian pre WWII army.
cross on cap is according to my findidngs added later as symbol for the weapon and amunition issued to chetnik batalions in serbian pre WWII army.