I spent a lot of time researching this question and the most authoritative thing I found was a LETTER which I believe was written by a state attorney (AG?...I don't remember exactly) expounding on his opinion of the MD regulations. Not exactly authoritative, and there was no way to verify if this letter was even written by whom it was claimed to be. I am quite sure though, that you can order high capacity mags online as long as you have them delivered to an address in a non-restricted state. Then go pick them up yourself. As far as "transferring" is concerned, the word is legally vague so I don't know for sure if it applies to having a friend mail them to you. There are a lot of grey areas in the MD statutes. From the looks of things, the MSP have the last say in enforcing existing or proposed legislation. Best to play it safe and pick them up in person and drive across the border. Or convert everything to 10 round magazines.