They were made by the Germans and sold to Iran.
Dropped vertically, lands horizontally without breaking a wooden bed stand, virtually without a scratch after knocking a (round) hole three times its length in a concrete roof? Having worked with various air-dropped munitions, Ive seen some weird stuff, but this is truly amazing!
The fins, even improvised would have given the round a relatively straight downward trajectory, and it would have punched straight down through the roof and embedded in the ground. The path of travel cannot be reconciled with physics. Simple observation proves traveling in that path would have resulted in a skip off the roof.
I recently sold an old propane tank that was just about that size and it weighed well over 200 lbs empty. Dropped from any significant height, it would crush whatever it landed on. I knowit landed vertically, but became airborne when the released has rocketed it across the house after the evil djinn was released.