I have a 64/66 Springfield picked up about 60 years ago that falls right into the Bannerman quagmire. I just started researching it and it's hard to tell a parts gun from a early conversion, regardless the primary reaction when it comes to U.S. Springfield Trapdoors, is their authenticity, and to get a 'realistic' interpretation of the Rifle one would have to consult a Springfield expert....
It did seem that anything post 1870 was 'less likely' to be a Bannermann(specific guy/co in the 50's? that set up shop near the Armoury and bought old stock and put together brand new old guns).
Is there a date on the lock plate, or a different date other than the model number on the trap mech?

Here's mine, re-blued 1950's at Long Branch Arsenals.

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