In fact, the .275 Rigby made before the war came out from the Oberndorf factory as barrelled actions fully finished in the white and proofed while Rigby only intervention was limited to stocking, sighting and finishing.
The .275 used intermediate length action and, to date, all the ones I got in hands had this type of floorplate, a magazine found on commercial C-Types as well as quite a few other civilian models.

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