German Rifled bbls were often marked for the "Bore" size by gauge in this era. Is there a mark such as 99.7 or 91.83 etc on the rifle bbl? These were as best as I can determine only checked to the largest plug which would enter in .010" increments, so are not really very accurate, but can tell some. A larger plug would enter a .38-40 than a .38-55. I believe that bullet dia for original .38-55's normally ran about .378" rather than .375" though.

Miller/TN
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