The "Old" standard short chambering for 12 ga was 2 5/8". Several American companies made guns with 2 5/8" chambers & specified they were for 2 3/4" shells.

As I recall all of my Lefever Arms Co (Syracuse) 12 gauge guns with the large cocking hook have 2 3/4" chambers. I have one which is the earlier two-hook design, Ca 1892, which has the shorter 2 5/8" chambers.

As per Researchers post, the better makers of American doubles would cut any length chamber to order up to about 3Ľ" as I recall.

Miller/TN
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