I learn something every day. I know for fact that 22LR and WMR are different diameter as you just measured. I do not have any WRF to check for my self. I was getting my information on the WRF from an old magazine article in one of grandpa's 70's-80's era American Riflemans that I had clipped and saved. My appologies and you seem to know more than I, or them for that matter. :)