Insert BB Barrel into RAP4
Marker with the bigger bore in toward the marker.
2. Make sure the BB Barrel is aligned
flush with rubber grommet
Install Muzzle Brake and
tighten the 3 set screws. Make sure the set screws are tighten firmly to the
BB Barrel. It is also recommended to use adhesive on the set screws to
prevent the set screws from coming loose.