I saw this fibre container marked "Depth Charge Dummy". I picked it up, very heavy, unpacked it and saw what was similar to an 81mm mortar in size with no nose fuze, solid, and shrouded fin with a small propeller on the shrouded fin end. Black in color. I put it back and then was told I could not handle it ( thus I was unable to take a picture of it) but did take the picture of the shipping tube and inking. By this ink marking information, can anyone identify it? Sorry for lack of more info, but I am puzzled and my curiosity is large. Needs a seasoned Naval ordnance detective on this case.