Bro. King: your Smith's hang tag listed 2 1/4 Dram (1155 fps) with 7/8 oz. shot.
That load with Bulk Smokeless was about 7500-8500 psi; with Dense Smokeless 1000 - 1500 psi higher.

Hunter Arms Co. lengthened the 20 gauge chambers from 2 1/2" to 2 3/4" in 1936.

While some modern 20g plastic hull 2 3/4" shells are shorter than 2 3/4", I would still not use one in a 2 1/2" chamber



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