Just to clear up a bit of confusion.....that P on the front of the grip is NOT proof of a rebuild. It is proof of a reproof! A few un rebuilt late Inlands have that marking but show no sign of "rebuild". However, the chances that the carbine was rebuilt if it has that stamp are exceedingly high. Its like double P stampings on some carbine barrels. 2 Ps may be a reproof from a rebuild. On the otherhand, some "free issue" barrels were proofed and marked by the manufacturer then proofed a second time after they were placed on the completed carbine. Its not always so easy to tell which is which.