Toilets having Coriolis Effect? Nuh, uh. Nope! Plumbing's purely gravitational and crap floats downhill downhill via gravity with exception of pumps and lift stations. The spinning in bowl if any is self contained into a circular downward motion by directional containment and by gravity.
Wind usually has more effect on shooting than Coriolis Effect. Wind? Odd thing to notice on a windy day, depending on how plumbing system is installed and vented, can actually see water in toilet bowls raise and lower from the vacuum created through buildings roof mounted vent stack. Yah, I know, lotta crap!
flushes is amazing, now if that can be quintessential to how shots are affected and Bullets travel that would be incredible. 
