How are you swapping cameras within your Blueprint? I have generally used the node “Set View Target With Blend” called on the given Player Controller. Is the issue that the view changes, but it does not update based on the movement of your mouse / controller? There is an option to “Use Pawn Control Rotation” that may need to be ticked if so, but if the camera is on a separate BP from your pawn, you’ll have to forward the control rotations from there to whatever weapon camera is currently active.