ΔE 17.5, loose: different enough that you should pick on purpose. Phoenix Red is a little darker, much more muted than Bloodmoon Red. They are different kinds of paint: Army Painter Bloodmoon Red is a one-coat contrast-style paint and Reaper Phoenix Red is an opaque base/layer paint, so they won’t behave the same on the model even where the colour is close.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Phoenix Red is a little darker, much more muted than Bloodmoon Red. They are different kinds of paint.
The same difference applies the other way round: Bloodmoon Red is a little 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 Bloodmoon Red on the colour wheel See Phoenix Red on the colour wheel
All matches: Bloodmoon Red equivalents · Phoenix Red equivalents