If those bores look that good, it would send a red flag up to me. I would say that they have been honed out and would give the appearance of looking "chromed".
One thing I would definitely do is to have the bores checked. I don't know what Colt's minimal and maximym dimensions were, but I would say .729 for a 12 ga.

This is just my opinion, and if it were mine I would have them checked.

David