OK call me nuts, but I think I figured it out. This is an expert job. I haven’t completely figured out how they did it ,but it’s sort of incredible. What I think we have here is a byf 42 that was expertly manipulated into a banner ,to deceive. I believe I figured out the upper receiver and the frame, but unfortunately I can’t figure out the barrel completely. Something wasn’t sitting right with me so I investigated probably further, than I should’ve😆.The first thing that was really bothering me was the breech block. It is Army accepted ( firing proof , typing 5:30am 😆) . How is it possible that we could have a commercial toggle with an army accepted breech block they don’t mix together. So then I was trying to think maybe someone changed out the Middle toggle to make it more acceptable. But in the end you wouldn’t have a commercial toggle with a military breech block it would have a byf toggle. The second thing that bothered me was the eight on the upper receiver. I believe this gun was originally 6254. The first thing that clued me into this was the serial number of 63 stamped on the inside of the side plate. This indicates that the first two digits of the serial number should be 62. If you look at the serial number on the upper receiver the eight is very deep. I believe this number was recessed and then reset. The second thing that I had issue with was the number on the frame. If you hold it at certain angles you can almost see the number six under the eight. This is next level work. I can’t quite figure out how they redid the barrel but I believe I can see you some manipulation under the eight. I can provide photographic evidence to all of this ,but I believe this was an expert level attempt to make a banner