Statistically, this shell should be a point and click pen to any tank at this battle rating. 175mm of flat pen at 100m, 0deg. More pen than PzGr 39 at 500m. At 3.0, it can pen a Tiger 1 at 2km. Yet consistently, you will non-pen and shell shatter on any T-34 or any KV. I cannot tell if this is an overperformance of Russian armour issue, or an issue with the shell. Either way, this thing is absolutely miserable to use, and I find the Lago 1’s 37mm APDS to be far superior despite being objectively worse in every metric.
This is the protection map at 1800m vs the T-34. At under 500m and almost face-on, the shell won’t pen. This is purely anecdotal from me, but I’m sure the experience is identical for other people.