Troubleshooting GW contrast over metallics

[fresh obsidian]

Someone on reddit suggested doing a metallic base and contrast over it so I based the red bits with VMC silver:

Tried doing GW's Flesh Tearers Red with a brush and got predictably splotchy results.

Busted out the airbrush but the result looks terrible. Dull as you could imagine and BARELY a hint of the metallic underneath.

I did a 5:2 mix of Flesh Tearers Red and Vallejo airbrush thinner. Is this just what's to be expected of Flesh Tearers Red and I should try something else like a thin glaze of Mephiston Red, or Blood Angels Red contrast?

The look I'm trying to replicate is the dark/metallic red ofthis image

[pale olive]

Is flesh tearers red contrast?

You might be better off trying something like Tamiya clear

If you want to tint the metal try mixing it with the contrast instead of applying it over.