Shells offered in the 1939 Verney-Carron catalog
https://www.verney-carron.com/pdf/catalogue-1939-FR-Verney-Carron.pdf

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With Poudre T and Poudre K2, but Poudre M was still available for purchase on p. 52
Poudre K2 was introduced in 1937 with lower pressures
T for 12g is 2.2 grams = 34 grains = 3 Dr. Eq. with 1 1/8 oz. is 7,170 psi + 10 - 14%
K at the same load is 6116 psi + 10 - 14%
Possibly K2 was a Progressive Burning powder like DuPont Oval?

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