I am trying a version created by Andrea Roccati on his youtube channel and thingiverse files. My printer is fairly small and I couldn't print many of the other larger 3d printed versions.
Here is my first testing run. Using a 15rpm motor which works well here with the bullets but with the case setup is too fast. Going to try a 6rpm motor next.
https://youtu.be/7waxCZSyEbk
Credits to Andrea Roccati
https://www.youtube.com/watch?v=NS7eX6uU6wI
https://www.thingiverse.com/thing:3438003