My CZ-75BD 16 round mags will fit and work in my CZ-100. BUT, the 10 round mags that came with the CZ-100 will NOT fit in the CZ-75BD, there too short. The 75's mag stick out about 19mm out the bottom of the 100! The CZ-100 also fires and loads Rem 115gr 9MM JHP (the green and white box) fine, but the 75BD jams about every 2-3 rounds. I have order a 26 round mag from CZ-USA, I want to see if it will fit my 100, now that would be cool!