@ apex: he said that sturmgeschütze could only fire their main-gun in "den unteren Winkelgruppen von ca. -3° bis +20°" ---> he didn't mention specific angles for different sturmgeschütze but told me in general about it...
...and he said that he never saw sturmgeschütze in indirect fire support role, only direct fire support role, with the sturmgeschütze having LOS to the target.
he also told me a lot about the very deep russian defences at Kursk, and that the german Panzer-spearheads had advanced to deep into enemy territory without infantry support covering their flanks.
My grandfather said that german soldiers had the impression of "drowning" in the vastness of the russian country...and that german forces were too few compared to russian forces...the russian artillery for example was at some areas 12 times the number of german artillery...
Trommelfeuer got a reaction from beersmurff in no indirect fire with SU-85 / 100/ 122 / 152 ?