Well, my beard was thick and copper-red too (I had to get hundreds of hours of electrolysis, it completely sucked), but my hair is brown. Claire and Clinton are drawn to suggest something closer to Rupert Grint's coloration than mine.
It sounds like we have very similar coloring. My hair is brown and my beard is (was) thick and slightly reddish-brown. I wouldn't call it copper red, but enough red to be noticeable. At my current age of 53, the beard is more gray than brown, but the hair is still almost entirely brown, with only very occasional strands of gray. (My father's hair was still salt-and-pepper, in about equal amounts, when he passed away at 72, and he still had a full head of hair, so I have no worries about going bald.)
My twin sister's hair was indeed copper red, or maybe auburn would be closer, and gorgeous, but she didn't have the ultra-pale skin and freckles commonly associated with "gingers", e.g. Rupert Grint. We're 1/4 German, 1/4 Polish, 1/4 English, and 1/4 Scottish, so I figure the red hair came from the Scottish part. Nobody else on either side of the family had red hair that I can recall, though.