In pocket billiards a carom shot is defined as a shot in which the cue ball hits an object ball which then hits another object ball before going into a pocket. An example shot is shown in the diagram below.
The 5-ball does not have a straight path to the corner pocket. The only way to pocket it is to carom it off the 9-ball.
HOW TO AIM A CAROM SHOT
To pocket a carom shot, you need to determine the spot on the table where object ball A needs to strike object ball B so that object ball A goes into the pocket. The diagrams below shows you the step by step process of aiming the carom shot shown in the example above. First, you need to determine where the 5-ball (object ball A) needs to strike the 9-ball (object ball B) so that the 5-ball is pocketed in the corner pocket. A way to do this is to determine the tangent line or the imaginary line that runs from the edge of the 9-ball to the pocket. See illustration below.
After determining the tangent line, the next step is to determine the imaginary ghost ball spot where the 5-ball needs to strike the 9-ball. To determine this spot, find the point of contact between the 5-ball and the 9-ball. The “point of contact” is where the tangent line touches the edge of the 9-ball. Simply mirror the imaginary ghost ball on the other side of the tangent line and you get your aim spot. See illustration below.
The last step is to simply aim at the 5-ball with the cue ball so that it goes to the aiming spot determined in step 2 above. This will not be explained in detail here because it has already been explained in previous articles about aiming. (See How to Aim – Contact Points and Ghost Ball).