ΔE 6.5, close: similar, with a visible difference side by side. Great Hall Grey is a little lighter than Light Gull Grey FS 16440.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Great Hall Grey is a little lighter than Light Gull Grey FS 16440.
The same difference applies the other way round: Light Gull Grey FS 16440 is a little darker.
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 Light Gull Grey FS 16440 on the colour wheel See Great Hall Grey on the colour wheel
All matches: Light Gull Grey FS 16440 equivalents · Great Hall Grey equivalents