2017 Helix Upgrade Kit
If you have a 2016 Helix magazine magazine or older you can upgrade your Helix magazine to the latest version. The upgrade kit comes with a set of internal shell, door, and door return spring. This upgrade will help the projectile to feed better and the door to shut easier. It will improve the overal operation of the magazine.
2017 Helix Upgrade Kit: https://mcsus.com/products/2017-helix-magazine-upgrade-kit