Following World War Two many, if not most model 1911 and 1911-A1 pistols remaining in the government’s hands were rebuilt and refurbished – both at arsenals and in the field. The original maker’s names were not marked on the frame, just the slide – and slides were often changed without any attempt to put them on a matching frame. Consequently these guns lost their identity. To tell which contractor made a particular frame you need to know:
(1) The serial number: Because serial numbers were assigned in blocks to the different contractors so in theory (but not always in practice) no two guns would have the same number.
(2) The inspector’s initials: Because certain inspectors were assigned to certain companies.
If you look under the slide stop you will see the initials; F.J.A. – these stand for Col. Frank J. Atwood, who inspected pistols made at Remington Rand and Ithaca. If your pistol has a serial number falling within a block assigned to Remington Rand this would tend to confirm that your gun is original as built, and not an arsenal rebuild. As such it is worth considerably more then a rebuild, as relatively few such guns escaped the rebuilding process.