ΔE 6.3, close: similar, with a visible difference side by side. Steel Legion Drab is a little lighter than WWI British Khaki Brown Base.
Usually, if you are not matching paint already on the model. Close match (ΔE 6). Steel Legion Drab is a little lighter than WWI British Khaki Brown Base.
The same difference applies the other way round: WWI British Khaki Brown Base 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 WWI British Khaki Brown Base on the colour wheel See Steel Legion Drab on the colour wheel
All matches: WWI British Khaki Brown Base equivalents · Steel Legion Drab equivalents