In my limited experience measuring 12g Flues chambers, 2 1/2" would be atypical

Courtesy of Researcher:
The last Flues period catalogue (1925) states "Unless otherwise ordered Ithaca 28 Gauge and 20 Gauge guns are chambered for the standard 2 1/2 inch shell, 16 Gauge and 12 Gauge for the standard 2 3/4 inch shell and 10 Gauge for the standard 2 7/8 inch shell."
No earlier Flues period catalogues mention chamber lengths.

What is the date of manufacture?



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