ΔE 9.4, close: similar, with a visible difference side by side. Dark Gunmetal is a little lighter than Silver Blade.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Dark Gunmetal is a little lighter than Silver Blade.
The same difference applies the other way round: Silver Blade is a little darker.
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 Silver Blade on the colour wheel See Dark Gunmetal on the colour wheel
All matches: Silver Blade equivalents · Dark Gunmetal equivalents