Bill Flemming, in his book "British Sporting Rifle Cartridges" lists bullet weights from a 200 gr Velopex to 320 gr. The 270 is most numerous followed by the 300. Kynoch and Eley each listed only one loading of the 200 with 40 gr of Cordite. Eley had another using 40 gr of Modite. Kynoch shows only one load using the 320 gr bullet and 40 gr of Cordite. Overall powders range from 37 gr of Cordite to 40 gr with most loads being in the 40 gr weight. Powders listed are Cordite, most often, in 40 gr, Axite, 2nd most at 39 gr, and Modite at 40 gr. A total of 48 loads are listed using various bullets and powders between the two manufacturers.
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