ΔE 10.5, fair: the same colour family, but not a straight swap. Bright Gun Metal is a little darker, more saturated than Plate Mail Metal.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Bright Gun Metal is a little darker, more saturated than Plate Mail Metal.
The same difference applies the other way round: Plate Mail Metal is a little lighter, more muted.
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 Plate Mail Metal on the colour wheel See Bright Gun Metal on the colour wheel
All matches: Plate Mail Metal equivalents · Bright Gun Metal equivalents