Summary

Printed at 0.2mm resolution w/brim (by default and almost certainly not necessary). I used PLA only because I ran out of PETG. Both files are the same, I think the 3mf file unpacks upside down. You do want the open holes side up, either file. I load mostly buckshot, some slug, very handy so print two so you can load safely in stages. Not really needed for bird shot as the hull start to finish can be done never leaving the press. About a 6 hour print, standard PLA BASIC bambu Labs print profile, A1 Mini (Local LAN only, the CCP is not our friends right now), still have the CR-10 for big stuff.

Didn't see on these on this site so I made on in freecad, way easier than a few years ago.