ΔE 8.3, close: similar, with a visible difference side by side. Cobalt Violet Grey is more saturated than Regiment Grey.
Usually, if you are not matching paint already on the model. Close match (ΔE 8). Cobalt Violet Grey is more saturated than Regiment Grey.
The same difference applies the other way round: Regiment Grey is more muted.
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 Regiment Grey on the colour wheel See Cobalt Violet Grey on the colour wheel
All matches: Regiment Grey equivalents · Cobalt Violet Grey equivalents