This is a 28mm model of the Red Army's 37mm AA gun, Model 1939.
https://en.wikipedia.org/wiki/37_mm_automatic_air_defense_gun_M1939_(61-K)
I started with Kpi's model of the Bofors, and adapted his file to represent the Soviet gun. I separated the model, and re-crafted the gun mount to represent the Russian gun. Likewise for the recoil system.
First thing to do after printing the parts, please glue the Gun mount to the gun mount bottom (both are approx 39mm). This gun mount will then sit on the actual gun base.
I tend to sacrifice accurate scale on smaller parts in favour of making the model more robust, but I did include the various elevation wheels and sights represented on the actual gun. I made the gun barrel movable; although do take care mounting it in the pivot points. I made a trough in the gun mount to help ease it in.
The wheels/tires (thanks to kpi's excellent design) have a "flat spot; please make sure that goes towards the ground.
If you have any questions or suggestions, please drop me a message.
Thanks