ΔE 6.9, close: similar, with a visible difference side by side. Ammo Pouch Brown is more muted, cooler than British Uniform.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Ammo Pouch Brown is more muted, cooler than British Uniform.
The same difference applies the other way round: British Uniform is more saturated, warmer.
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 British Uniform on the colour wheel See Ammo Pouch Brown on the colour wheel
All matches: British Uniform equivalents · Ammo Pouch Brown equivalents