Hola
A couple of my friends bought 3D printers. Been experimenting with magazine plates.
This is a CZ 97b 12 round magazine. It fits 14 rounds but with 13 or more rounds the follower will exit the metal frame and jam on its way up - so I will shorten this by 10-15mm. It's a kind of trial-and-error process. My goal was to have a 12 round magazine, twelve being the maximum that will still hold the follower inside the metal frame.
I will post updates as things progress. At the moment my cz's magazine catch is broken so no updates for a week or two.