On the Facebook group Cartridge and Ordnance Curio & Relic Collectors member Samuele Moroni posted a photo of some SAKO boxes for cartridges derived from the 7.62x54mmR (7x53R, 7x54L, 8.2x53R, 9.3x54R) but one stands out as an oddball, the 3.6x53R/K box. Moroni’s photo of the boxes is shown below:
The box in question is in the blue rectangle on the left.
Photo slightly enlarged:
I know very little about these rounds (not my area of collecting but I’m always intrigued by unknown cartridges) and I know nothing on the 3.6mm round so can anyone shed some light on this cartridge? What is the meaning of “K” in 3.6x53R/K?