I searched this forum and the web in general for a conglomeration of the effect of different malts, particularly various darker ones, on head colour and didn't come up with enough.
Thought I would make this long-running thread for the purpose of archiving some observations after my most recent brew day.
Used Black Patent malt at 2% in a beer and saw that it ended up a really nice chestnut brown.
I've brewed and bottled a whole bunch of beer recently, and will put up some results in a few days.