ΔE 6.5, close: similar, with a visible difference side by side. Russian AF Grey N.3 is a little darker than Typhon Ash.
Usually, if you are not matching paint already on the model. Close match (ΔE 6). Russian AF Grey N.3 is a little darker than Typhon Ash.
The same difference applies the other way round: Typhon Ash is a little lighter.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Typhon Ash on the colour wheel See Russian AF Grey N.3 on the colour wheel
All matches: Typhon Ash equivalents · Russian AF Grey N.3 equivalents