Wont work at all or just really tight? Most are a little over molded. Mike's MD 20 fitting post, with video. Works/basic for all mag fitting. Try it and get back, if not working.
A complete no go. I have a 20 rd drum the someone shaved a bit and that one is closer, but still not enough to force. The mag that came with it has about twice the lip. Im afraid if i shave too mush of the plastic, there wont be enough for continued support on the mag. I am considering filing some of the mag lock down a bit, then some of the mag, maybe to meet half way.