George is likely correct

My 06' 00


A Baker


A Colt 1883


A Parker VH


Comparing another sidelock (the Baker) and two boxlocks (Colt and Parker), it is apparent that there is a 1/2" of exposed wood between the receiver and the trigger guard on the LC. It seems likely the wood scarification is simply the result of abrasion and crushing, the accumulation of dirt and oil from gloves and fingers, and possibly being hung on a nail in the barn.

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