ΔE 6.7, close: similar, with a visible difference side by side. Russian AF Grey N.3 is a little darker, more muted than Barley Gray BS4800/18B21.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Russian AF Grey N.3 is a little darker, more muted than Barley Gray BS4800/18B21.
The same difference applies the other way round: Barley Gray BS4800/18B21 is a little lighter, more saturated.
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 Barley Gray BS4800/18B21 on the colour wheel See Russian AF Grey N.3 on the colour wheel
All matches: Barley Gray BS4800/18B21 equivalents · Russian AF Grey N.3 equivalents