I haven't tried them but have seen some Youtube videos where people seem satisfied with Eastwood powders for coating cast Boolits.
400*f doesn't worry me a bit.
But I don't make jigs with weed guards.
I would guess though a base hole pin and epoxy them in would solve that.
For some good powders at great prices check out Cadmans custom jigs.http://cadmansjigs.weebly.com/powder-paint.html
Hard to beat $7 per pound.
I have used several of his paints and am very satisfied.
And he is a member here.
Color choices are limited though.
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