ΔE 22.2, loose: different enough that you should pick on purpose. Dark Gunmetal is noticeably darker, much more muted than Platinum Crown.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 22). Dark Gunmetal is noticeably darker, much more muted than Platinum Crown.
The same difference applies the other way round: Platinum Crown is noticeably lighter, much 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 Platinum Crown on the colour wheel See Dark Gunmetal on the colour wheel
All matches: Platinum Crown equivalents · Dark Gunmetal equivalents