Raimey: here are pressures for 1 1/16 oz. loads reported by Major Sir Gerald Burrard, The Modern Shotgun, Volume II, The Cartridge, 1955 3rd Revised Edition pressures converted from Long Tons/ Sq. Inch at 1
12g 2 1/2 33 gr. Nobel Smokeless (3 Dr. Eq.) with 1 1/16 oz. - 7,885 psi
12g 2 1/2 33 gr. C&H Smokeless Diamond (3 Dr. Eq.) with 1 1/16 oz. - 8,288 psi
12g 2 1/2 31 gr. Smokeless Diamond (2.8 Dr. Eq.) with 1 1/16 oz. - 7,179 psi

Modern Kent/Gamebore English Field 12g
2 1/2 1 oz. Traditional Paper @ 1295 fps - 6526 psi
2 1/2 1 oz. Pure Gold @ 1295 fps - 7832 psi


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