Quick and dirty hack to get the Soviet Weapons Chris released the artwork for into the game.
All of the Soviet weapons have been given their own ammo types with the exception of the shotgun and the rocket launcher.
Stock weapons were left alone. In general the magazine sizes are smaller than stock weapons (sniper, shotgun, pistol).
The shotgun I think was just supposed to be a 'generic Soviet shotgun' but the closest in appearance that I was able to find is a Baikal MP-153 (semi-auto gas operated):
http://world.guns.ru/shotgun/rus/mp-153-e.html
I could not find any information as to when this shotgun was first manufactured so I have no idea if this is "lore friendly"/historically correct. Also all weapons use existing sprites so although it does not look like a pump action in the artwork you will still see your Xenonauts cycling the action.
To remove run the soviet_uninstall batch file in your Xenonauts install folder.
Have fun!
https://db.tt/crGSCj4n