In this video I will show you how to install the inner oring on the transfer port using a tool that I designed.
The tool is free to download and can be 3D printed. Note that the walls on the tool must be close to solid.
The file is for a 177 but can be adjusted to any caliber by your 3D guy. I will not upload files for each caliber.
You can find the file here:
https://www.thingiverse.com/thing:619...

Also in this video I will talk about sharing tunes for the FX Impact M3 and what to take into consideration in terms of different components mounted on your gun.

Enjoy!