Plunger Spring Mod (Required for rHop Mod)Updated a month ago

Plunger spring mod aims to improve semi-auto performance for rHopped barrel groups.
It prevents pre-compression issues which can affect BB placement inside the hopup chamber.
You need to use the flat hopup rubber bucking to work with this mod.

Installation Guide:

Mill the back end of hopup chamber to around 10mm, with a 5/16-inch (8mm) width bit.

Finished Surface.

Make sure the plunger spring fits.

Verify to make sure the plunger spring can be fully compressed.