anyone else find their RC score way more volatile than LR?

my LR scores r super consistent, usually -5 after many at -7/-6. but RC is all over the place. last three PTs i went -2, -9, -13. same study habits, same timing strategy, just wildly different results depending on the passages. is this normal or am i doing something fundamentally wrong? feels like LR rewards consistency but RC is just a coin flip sometimes.