The CEO of PMC Wagner posted this on social media a few days ago, complaining that the Russian Ministry of Defense was not giving his mercenaries enough ammunition. Today, the order was reported by the CEO as fulfilled but if this document is accurate it actually reveals how much ammunition the Wagner Group is using in offensive operations.
In a 10-day period of attacking, the document claims that Wagner uses 187,000 shells and rockets. That's over 580,000 shells/rockets a month.
Since Wagner is holding back approx. 30% of the Ukrainian frontline forces, with minority assistance from army and separatist forces, perhaps a full Russian offensive stance all across the front would be in the region of 2 million shells/rockets a month.
So claims from NATO, Ukraine, and other analysts that Russia used 9 million or so artillery shells/rockets in 2022 can be measured against this.