Other than the usual 5 round capacity, I have both 20 & 30 round factory Ruger Mini-14 magazines. I don't like or use the 30 round mags as they are too bulky and rattle around. They feed flawlessly though. Also some extra info on the Ruger factory magazines. Before the Federal high capacity ban Ruger changed the floorplate configuration on the 20 round mags. The later pre-ban mags seem to have a non-removeable floorplate which is held in place by a solid pin. This pin is visible through a hole in the side of the mag body. The ones I prefer have the usual removeable foorplate, no pin retaining the plate, and stamped with "RUGER Mini 14" and the Ruger logo under it. Both versions use the same high quality follower and spring, not the junk that USA Mag or other manufacturers use. The Mini-14 was also chambered in .222 as well. I don't know if the .223 mags will work in these rifles too. My guess is they will, but the factory mags I have do not have the calibre stamped on them. I hope this helps.