Considering the fact that your 22 small journal has no markings It's not at all from Winchester. I have never observed a 22 small journal which was not precisely the same outdoors dimension as 22lr mag. I can’t visualize how a mag, such as you described, could risk be safe https://highimpactrounds.com/product/winchester-defender-12-ga-2-75in-1-oz-rifled-slug-00-buck-1150-fps-10-rd-box/