I don't know either. I have 2 New Hampshires (at least that's what the breeder told me they were). There's not a whole lot of difference, I don't think. New Hampshires were developed from Rhode Island Reds. I had done some research before I got them but I don't remember a whole lot of it right now.
Thank the hatcheries for that. Originally a heritage type is unmistakable with telling the two apart.
In general most New Hampshires, when grow, turn an orange color while Production Reds are more of a reddish orange. Production Reds are also usually less fluffy at the thighs.
Also - It's New Hampshire. No "red" in the name, that's just something hatcheries put in.
Kathyinmo has the most beautiful heritage New Hampshire's ever. They are on my one day wish list. Have a look see. Notice the coloration in the hackle feathers.
See how different they are supposed to look? Like Illia said, hatchery's don't breed for standard and you get mixes and yucko. Hard to tell hatchery "breeds" apart sometimes!
I was just trying to make sure everyone knew I was talking about the two reds, and not the RIW. Lol.
But I will post pics of my RIR hens and see what everyone thinks. I have a feeling someone will say production reds, but that is also something I can tell apart...