The topic of accuracy and precision of Soviet guns comes up a lot. Stereotypically, these guns are depicted in media as being unable to hit the broad side of a barn. Records of trials show otherwise. Here is a record of one such trials at various distances.
Unfortunately, the dispersion isn't nicely mapped out like in other trials, but we can use the known diameter of the hole (152 mm) to estimate it.
First, 200 meters. The rounds are closely clustered together inside the bullseye. Its radius can be estimated at 2 and a third calibers, or 350 mm. At this range a SU-152 gunner can hit any target without difficulty.