Considering that your 22 brief journal has no markings It's not from Winchester. I haven't observed a 22 limited journal that was not a similar outdoors dimension as 22lr mag. I can’t think about how a mag, like you explained, could possibility be safe when inserted. A photo can be https://highimpactrounds.com/product/winchester-defender-12-ga-2-75in-1-oz-rifled-slug-00-buck-1150-fps-10-rd-box/