- Apply red ochre primer with natural drying oils (or Oksol NKTP OST 7474/581)
The recommended concentrations of the primer (OST 7814/753) are as follows:
- 40% dry primer (or appropriate amount of mixed primer)
- 55% of natural drying oil
- 5% dessicant #64
The primer is applied using the commonly used method at the factory, depending on equipment. After primer is applied, the item should be dried. If possible, dry in hot conditions at 80 degrees for 2 hours.
This was, (not by me), translated from;
http://yuripasholok.livejournal.com/2726128.html
The original document is dated from 1941. Disregard further discussion and images on page about post-war colors. I have read accounts of other colors being used as well, but I can not confirm them.
Note that this refers to "red ochre", Fe2O3, (A variant of ochre, (Iron(III) oxide-hydroxide) containing a large amount of hematite, or dehydrated iron oxide, has a reddish tint and is known as "red ochre", not "red oxide" which refers to lead oxide, Pb3O4.
On page 34 of The Eastern Front, by Zaloga and Grandsen, they state that the only case where T-34s "might" have rolled out unpainted on a "limited extent" was from the STZ factory in the fall of 1942 during the battle of Stalingrad, when the factory was still located within the city.
As for vehicles being painted without being primed, I have no information to support or refute this statement.