Pool glossary · Aiming & Physics
30-degree rule
What is the 30 degree rule in pool?
The 30-degree rule says that a naturally rolling cue ball deflects about 30° from its original direction after a half-ball hit, and stays close to 30° across a wide range of cuts around half-ball.
In more detail
Use your hand as a 'peace sign' (V between index and middle finger) to visualise the 30° path. It helps predict carom, kiss and scratch lines, and to plan follow position.
People also ask
When does the 30° rule not apply?
With stun, draw or very full or very thin hits. It is for natural roll near half-ball cuts.
Train it at the table
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