From the 1896 Rules of Proof. 42 gr. "E.C." or "Schultz" would be 3 Dr. Eq.



Major Sir Gerald Burrard in the 1944/1947 Second Edition of The Modern Shotgun, Vol. III The Gun and the Cartridge, states immediately after WWI the standard for 2 1/2" & 2 5/8" shells became 1 1/16 oz. with 42 grains (Old) Schultze Bulk (3 Dram), 36 grains E.C. (Improved) or 33 grains Imperial Chemical Industries (Eley & Kynoch Cartridges) Smokeless Diamond powder.

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