The Praetorian 1C CIWS turret can aim straight up, despite the presence of physical stops in the model that should restrict its elevation angle. This causes clipping.
The apparent solution is to either limit the elevation angle of the gun to match the model, or adjust the model to remove the stops.
The attached screenshots show the gun mount clipping through the stops in the base when elevated.
Gun depression is appropriately limited and does not cause clipping.