Rare Arms Shell and Chamber

This is a shell design for The Rare Arms AR-15 Airsoft Gun. 

These shells hold 3 BB's each, turning it into a shotgun. With one BB the accuracy is hilariously bad but with 3 the grouping become much tighter. I only play CQB and the gun doesn't have the power to hit a normal rifle range anyways.

I use a .4mm nozzle and print with ABS. If you are having layer adhesion issues with the bed, increase the brim size. If the shell is breaking from the brim you may need to use support instead or edit the file and add a thicker brim. The intent was to minimize post processing required. The shells will retain BB's on their own if printed properly. I modeled 3 tabs. It was intended 

I've only used these shells in real Lancer L5 AWM mags with cut springs. They appear to fit in the rare arms magazine but I haven't tested.

Also included is my file for a chamber. Mine wore out during experimenting and the store took forever to stock. It requires breaking in. I cycled a few shells and it wore grooves into it. 

Included is the chamber pin I made after I lost mine. 

Modeled with Shapr3D