A few more details about this gun; the screws are American/English standard, not metric suggesting it was manufactured in USA, the roll die engraving is excellent, the inside of the wood grips is marked in ink similar to the "real guns", something I did not know? It was suggested, by my friend, that I get the metal tested in the barrel and cylinder as my friend has done with the parts referenced in the above post. That will give us a digital fingerprint in which to compare with the Colt parts. We have access to the equipment. What we are looking for is a gun manufactured along the timeline of the real Colts in the USA. Also, if you know of American reproduction guns made from 1960 thru 1980s please share. I may be wrong, but 2nd generation Colt Walkers were contracted out to Italian firms and parts are metric.