I think here is a fundamental misunderstanding by some of you:
The coriolis effect, gyroscopic effect, and centrifugal force are not some kind of "extra physics" or "magical effects" that occur on top of conservation of mass, energy and momentum. These effects are just apparent phenomena when analyzing movements in rotating reference systems and are caused by the conservation of mass, energy and momentum.
So the question "is it coriolis, or conservation of momentum" doesn't make sense, because the latter causes the first.