Originally Posted by
stencollector
To add to the anomaly, I have a 1956 dated rifle that also has the extra digit on the end of the serial number. Mine is 90L44220. The bolt is not scrubbed, nor is the receiver...the serial looks perfectly normal and is of the more conventional size for a LongBranch. It has a target swivel, and the barrel is above the bedding area so I assume it's center bedded.
I also have a 55 dated receiver with 30-06 uncontoured barrel blank, but it is very unconventional and was used as a test bed for ballistics testing. No serial numbers on that one.