ΔE 9.9, close: similar, with a visible difference side by side. Orange Tone is a little darker, more muted than Light Rust. They are different kinds of paint: AMMO by Mig Light Rust is an opaque base/layer paint and Army Painter Orange Tone is a wash/shade, so they won’t behave the same on the model even where the colour is close.
Usually, if you are not matching paint already on the model. Close match (ΔE 10). Orange Tone is a little darker, more muted than Light Rust. They are different kinds of paint.
The same difference applies the other way round: Light Rust is a little lighter, more saturated.
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 Rust on the colour wheel See Orange Tone on the colour wheel
All matches: Light Rust equivalents · Orange Tone equivalents