Because your 22 short journal has no markings It's not from Winchester. I have never found a 22 shorter magazine that was not a similar exterior dimension as 22lr mag. I can’t visualize how a mag, such as you described, could risk be safe when inserted. A photo might be https://highimpactrounds.com/product/winchester-defender-segmented-slug-12-ga-2-75-in-1-oz-1600-fps-10-rd-box/