I believe Mike Campbell contacted Tom Armbrust about pressure testing pre-WWII loads in the early days of the 16g Society. He'd already done so and the results were quite inconsistent. Occasionally, possibly related to hardening of the wad or paper hull, the pressure was increased. He felt that the primers failed before the powder. I would certainly check the bore after each shot.

Last edited by Drew Hause; 11/13/11 10:30 AM.
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