The proof marks date 1904-1925
13/1 indicates bore .719" - .728"
Pigeon loads of that era were typically 1 1/4 oz. 3 1/2 Dr.Eq. - probably not a good choice now with 100 year old wood.

Cornell Pubs has a 1903 catalog repro which is available as a PDF
https://cornellpubs.com/product/363...m4DsgM4vYSgy2hkJeqwb-Ga5KAJwy1_bz8yV4noc

1905

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