That is correct. The Mini 14 mag catches at the back of the magazine akin to theI don't have a Mini-14, so correct me if I'm wrong, as I don't know the answer for certain. But isn't the Mini-14 mag proprietary to the firearm? You can't just throw in NATO 5.56 x 45 STANAG 4179 mags into the gun, can you?
M-14 magazine. Some outfit made a "Universal" magazine that would work in either the AR or the Mini. As I recall, it wasn't good in either.