Well, It depends on what the parents would have for genetics, I would suggest you check out this website: Color Calculator
Its really great. It tells you exactly what you might get!
Also, on the dun argument, He could possibly be a dun, the first pic of him running, looks edited and brightened, so your not getting his real color, he looks more of a dun in the second one, I see "edged" ears, the dorsal strip in the first one seems pretty solid to be counter shading on a bay, and I can see a hint of striping on the legs, FYI, duns don't always have leg barring, or even dorsal stripes. But I think the ear edging points, IMHO, to a definite dun.