It was not a factory challenge for that model. Probably Imaginative crafting of a standard stock. Pictures would support to find out the appx calendar year your rifle was created. forty four It was presented from about 1959-1963. Another defining characteristic of your JTSS is it came using a Winchester https://highimpactrounds.com/product/winchester-super-x-270-win-150-gr-power-point-2850-fps-20-rd-box/