Shotgun Barrel Brush Adapter

I bought a 12 gauge cleaning brush only to find that the threads (5/16-27) are larger than standard rifle cleaning rods (8-32). You can buy shotgun cleaning rods, or a thread adapter, but you can also 3D print one! Just bring your own 8-32 screw.

I used an 8-32x0.5" hex head screw, but most screws would work as long as the head diameter is smaller than the hole for the 5/16-27 threads on the brush.

After printing, screw in the 8-32, then screw in the brush you want to use. You will need two pliers to hold onto the adapter and the brush at the same time. The larger hole isn't threaded (too fine for FDM printing and not really necessary IMO) and may not stand up to repeated use, so you're probably better off making one for each brush you have and leaving them attached.

Original CAD file is on Onshape.

Print with 0.2mm layer height or smaller.