I mentioned in another thread that Numrich had an aluminum base magazine listed. I had an order in to Numrich so I had them add the Luger magazine to it -
Magazine, 9mm/7.65 Para
(.30 Luger), 7 Round, Blued
New (w/ Aluminum Bottom)
Product #: 466090
It came in today. As you can see from the pics below, it has a metal follower, button, and base.
I set it up in my mill with the 5/8" ball end mill
('cause that is what I have 
) and proceeded to mill the finger depressions in the base. It was a tough cut. I had to use fairly strong pressure to get the end mill to cut. After I was done, I noticed that the pins were roll pins [split pins]. I knew they would drift out easily so I removed them and inspected the internal parts. I couldn't figure out why an "aluminum" base was so hard to mill. Even Zamak isn't that hard. ...D'Oh!... It's not aluminum! It's stainless steel! Last pic shows the base hanging from a magnet. Not as magnetic as the steel tube but enough iron & nickel to make it magnetic. And it's hard stainless; not soft.
No identifying marks anywhere. Flat checkered button. Round spring. Seems to function OK. Locks in place, button trips the hold-open. I still don't like the rings, but from now on, I'll stick to ball-milling plastic and aluminum, not these stainless magazines.
