Mid Mustard Khaki vs Gun Corps Brown

How close are they?

ΔE 6.3, close: similar, with a visible difference side by side. Gun Corps Brown is a little darker than Mid Mustard Khaki.

Can I use Gun Corps Brown instead of Mid Mustard Khaki?

Usually, if you are not matching paint already on the model. Close match (ΔE 6). Gun Corps Brown is a little darker than Mid Mustard Khaki.

Can I use Mid Mustard Khaki instead of Gun Corps Brown?

The same difference applies the other way round: Mid Mustard Khaki 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.