First of all dont kill me, I did not do any of the modifications on this gun. I have a 1911 frame pistol with a US&S slide and a frame with "United States Property" No 72822 markings. This pistol has been worked on extensively adjustable trigger, upgraded hammer, upgraded sights, extended slide release and safety, pachmayer grips, extended beaver tail, mag well. I will upload some pics. But my question is this, the slide is easy to identify as a US&S, but the frame...would anyone know the manufacturer of the frame with that serial number?