In all the books about it, it is described as a hand mortar, also if we look at the first picture, you will see "barutno punjenje", a special tube made out of cardboard, filled with propellent, wich pushed the mine out of the barrel, there was no rocket filling or anything...just a shot.
Vule, yours are model 56 mines, used for training, nice set, also with cleaning rodes for cleaning the inside barrel of mines.
There were 3 types of mines used in JNA, live one (model 57), training (model 56) and an inert mine, used in school (olska), wich was in light blue color.
Bye, Jure.