Feedneck twistlock insert
thingiverse
I've had these twist lock feednecks for paintball for many years and the insert pieces always seemed to break so easy. I made this and it works well enough, definitely works in a pinch but someone with better tools than me can probably perfect it.
Download Model from thingiverse
With this file you will be able to print Feedneck twistlock insert with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on Feedneck twistlock insert.