Hi G Dog, based on most of the information I have seen, I must agree that the Pietta 1862 is a copy of the 1861. However, I admit that I may not be 100% correct and that Colt may have offered the 1861 with a short barrel and called it an 1862 for a special police department order. I saw that reference somewhere, but can't again find it. IMO the jury is still out.
BTW, I have one of those Pietta 1862s and it is sure one sweet BP revolver. It offers fantastic handling and really fits my hand better than any other BP revolver I own. I can shoot .38 Special with that revolver. I'm seriously considering getting another. Old South has ~20 of them in stock so there is no immediate need to act soon.
Regards,
Richard