Soviet 4BO — Vallejo equivalent

I've found a good match for the WWII Soviet "Protective Green" 4BO paint in Vallejo ModelAir 71.010 Interior Green.

This was, apparently, the standard colour the tanks rolled out of the factory in (assuming they had time to be painted at all), though the recipe for the paint in the official records is fairly imprecise, so there was likely to be a fair bit of variation even among brand new vehicles.

A complicating factor, when attempting accurate colour matching, is that apparently 4BO darkened by chemical action as it aged. Or maybe it faded. Or maybe it was just dust in the photos that made it look like it had faded. There seems to be a bit of squabbling amongst the experts on this point.

From my point of view, all I'm interested in is that there were light green tanks and dark green tanks, and since this is the colour recorded by the Americans at the Aberdeen Proving Ground when they examined some Soviet armour during and after the war, this is the one I'm going to use for the lighter shade.

Zvezda KV1 (1941)

 Here'a another 1:100 scale (15mm) KV1 from Zvezda, a slightly later model than the previous one with a slightly better 76.2mm gun. ...