Component Local Rotation

Greetings!

I have a static mesh as a child inside an actor. Both actors will rotate to face towards the direction of a spring arm that is also part of the actor. For reference, here is a screenshot showing my hierarchy.

The rotation works fine when the actor is level in world rotation (so no Roll or Pitch, only Yaw values). This can be seen in the following screenshot.

If I look down or up (add values to the Pitch), the WeaponMount mesh will follow correctly, but if I THEN look left or right, the rotation starts to get weird.

I want the WeaponMount to always be ‘attached’ to the SubMesh parent mesh, while being able to rotate on it’s local Yaw still, but this clearly ‘detaches’ it as the WeaponMount being to rotate in unwanted fashion.

Is there a tried and true method to achieving what I am after?

Thanks in advance!