ΔE 13.4, fair: the same colour family, but not a straight swap. Russ. AF Grey N.8 is noticeably lighter, cooler than Gravestone Blue.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Russ. AF Grey N.8 is noticeably lighter, cooler than Gravestone Blue.
The same difference applies the other way round: Gravestone Blue is noticeably darker, 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 Gravestone Blue on the colour wheel See Russ. AF Grey N.8 on the colour wheel
All matches: Gravestone Blue equivalents · Russ. AF Grey N.8 equivalents