They're perfectly legal. Not worth it. I have a small collection of drum mags, and none of them work properly. A few might get ten or so rounds out before a FTE or FTF. The others, well... It's more like working a bolt action than a semi auto. Shoot, eject round, shoot, eject round, shoot, eject round, you get the idea. I'll stick with the 25 and 30 round banana mags. May not hold as much, but at least they function properly.