Under the 1896 Rules of Proof, the 16 bore Service charge was 1 oz. 2 3/4 Dram Eq. = 38 gr. Bulk Nitro powder with the following (+ 10-14% to converted to modern transducer) pressures:
C&H T.S. No. 4 - 7,480;
Schultze - 8,250 psi;
E.C. - 8,960 psi

Under the 1954 Rules 3 tons/ sq. inch = 8,938 psi by piezo transducer

Shells with those ballistics are the heaviest I'd use; lighter loads will be more comfortable.

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