Due to the fact your 22 small magazine has no markings it is not from Winchester. I have not noticed a 22 shorter magazine which was not precisely the same outside dimension as 22lr mag. I'm able to’t imagine how a mag, such as you explained, could probability be protected https://highimpactrounds.com/product/winchester-super-x-20-ga-2-75in-3-4-oz-rifled-hollow-point-slug-1600-fps-5-rd-box/