Hi Capa M4 Adapter

The STL file featured should fit an M4 magazine and mag catch with minimal modifications. This can be used to attach another magazine on top like a Hi Capa mag.


First let me start by saying this is a very intensive project. I used Vinyl Tubing, JB Weld, copper tubing, and an HPA tap to rig up a permanent solution to getting bb's from a M4 magazine, into the hi capa mag. I found plastic was not the solution for me in this situation as it simply warped and made the part weak.

1. Find some type of tubing that feeds BB's though smoothly and will fit inside the M4 Mag lip. You will JB Weld this, or fix it into place in some fashion to allow BB's to flow smoothly through while disengaging the spring loaded stopper.

2. I ordered Vinyl tubing on amazon to connect the tubing from the M4 mag, into the tubing of the Hi Capa Mag. Ideally, this tubing connects both tightly, while allowing for disconnection when needed.

3. Now you need to find a tubing to fit inside of the Hi capa