no and no. No a 22lr can not be shot from a 22 wmr. The 22wmr is a longer and has a larger diameter case and therefore has a larger diameter and deaper chamber so the 22lr will not fit in the chamber. And no a 22 wmr or 22lr barrel will not fit on a topper. A topper is a centerfire receiver and the firing pin is designed to hit the center of the case. The 22lr and 22wmr (and 17hmr) are rimfire and the firing pin is located to hit the rim of the case (hense rimfire).
Hope this helps!
later,
scruffy
