Some issues of Retro Arms CNC hopup chamber come with a tensioner nub that is 0.5mm narrower than it should be, so it wobbles left-right a lot, making the hopup inconsistent. I made this model tighter so it remains in dead center.
Also, my C-clip came without the tooth that keeps the inner barrel aligned at the right angle, so I had to make one myself.
After printing check if the nub can slide freely in the unit. If not, use X-ACTO knife to adjust the printed model to fit.
The author marked this model as their own original creation.