One of the problems with having a massive collection of WWII Soviet artillery is having enough men to man the guns.
Zvezda often gives only two or three crewmen for a gun that might need 8 or 12 men.
One way to solve the problem is to draft troops from other places.
The Airfix WWII Russian Infantry set is very old and very tired.
As a result most of the men from that set in my collection have volunteered to serve the guns.
Many of the old hard plastic Esci Russians are also transferred to the artillery.
Still more have been needed so I have been buying the Orion Soviet Artillery Crew set to fill in the gaps.