So according to the instructor who recently taught me the material of the CFSC and CRFSC and did my examination, there is no legal magazine size limit for semi-automatics if they are rimfire. The other day I saw some 50 round magazines for .22 rounds on one of this forum's affiliate's website, I forget which one, but is there anything bigger than that? What about drums? I know there are 100 round drums for both the M-16 and the AK-47, is there anything like that for a semi-automatic .22 rifle?