ΔE 13.2, fair: the same colour family, but not a straight swap. Camo Green is noticeably lighter, more saturated, cooler than Helmet Brown.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Camo Green is noticeably lighter, more saturated, cooler than Helmet Brown.
The same difference applies the other way round: Helmet Brown is noticeably darker, more muted, 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 Helmet Brown on the colour wheel See Camo Green on the colour wheel
All matches: Helmet Brown equivalents · Camo Green equivalents