Blaine, That is ridiculous. Common sence tells you that that would be impossible, as the entire premise of coriolis effect, deals with and varies with direction.
Now, not that this would ever matter from a small arms ballistics point of view, but, the effect from 100% at a north/south shot to 0% at an east/west shot could be roughly estimated by multipling the resultant vector times the sine of the angle from north/south. Gee, don't forget to add in the gyroscopic stability cause that's gonna throw a wrench in the equasion!
Regardless of the hemisphere, a shot fired tward the equator would impact west of it's intended point of aim, and a shot fired away from the equator would impact to the east.
Shots fired due east or west at the equator will have no resultant effect, and shots fired due east or west at any point away from the equator will exhibit a very small effect, spelled VERY SMALL, because of thier altitude varying. If the altitude is increasing, then, so is the southward component of motion due to the orbit not being geo-syncronous.
Since you have put me through this, my challenge to you is to either refute this, or, take a 210gr Berger 30 Cal bullet shot at it's advertised BC, at 2800fps, at an altitude of sea level, From the equator, due north/west (45deg), an impact at 1000meters exactly on target, with the target at exactly the same sea level altitude, and a nice easy theoretical GS of 1.0 . All indoors with no wind, 70 deg F, 70% Hum, 29.5Bar, and you tell me, how far the impact is affected by coriolis effect as opposed to the same shot fired due south east. Should be an easy one! You only need to calculate 1 of the 2 and multiply the result by 2. Simple!