Keith: I should have made it clear that these are modern piezo transducer estimated numbers based on the original LUP.

12g
1 1/8 oz. 3 Dram Equivalent of BULK Smokeless was 6500 - 7500 psi.
1 1/8 oz. 3 Dr. Eq. of DENSE Smokeless was 9000 - 10,000 psi.
1 1/8 oz. 3 1/4 Dr. Eq. BULK Smokeless was about 8500 psi.
1 1/8 oz. 3 1/4 Dr. Eq. DENSE Smokeless was 9500 - 10,500 psi.
16g 1 oz. 2 3/4 Dr. Eq. BULK Smokeless was about 7000 psi.
20g
7/8 oz. 2 1/2 Dr. Eq. BULK Smokeless was 8000-9000 psi.
7/8 oz. 2 1/2 Dr. Eq. DENSE Smokeless was about 11,000 psi.

Details here
https://docs.google.com/document/d/1F2sQuPm05IE4VWYYnCkvuXmYEzQoWd_SQgaAfUOZEFU/preview

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