Here's the Problem.........
Cue ball selection is very important which is why I have seven (7) different cue balls.
The official rules allow for a variation in weight of up to 1/2 ounce per individual pool ball........none of the balls have to weigh the same weight, including the cue ball.
So you can be playing with a cue ball that weighs up to 1/2 heavier than the object balls or even up to a 1/2 oz. lighter........a little over 14 grams weight variation is "permissible".
And all of the object balls can vary in weight so when you hit a heavier object ball with a lighter cue ball or vice versa, the object ball will still get pocketed....hopefully......but the movement of the cue ball although similar will produce different results on many types of shots played in a match.
Even the size of the balls can be different in circumference.....the rules allow for "sanctioned" differences in the size and weight of the pool balls, including the cue ball.That's why cue ball selection is important for many players, including the pros.
Matt B.
World Pool Billiard (WPA) Specifications:
All balls must be composed of cast phenolic resin plastic and measure 2 ¼ (+.005)
inches [5.715 cm (+ .127 mm)] in diameter and weigh 5 ½ to 6 oz [156 to 170 gms].
Balls should be unpolished, and should also not be waxed. Balls should be cleaned with a towel or cloth free of dirt and dust, and may also be washed with soap and water.
Ballscontaminated with any slippery substance - treated with a polishing or rubbing compound and/or waxed - must be cleansed and de-waxed with a clean cloth moistened with diluted alcohol before play.
A complete set of pool balls consists of one white cue ball and fifteen color-coded,
numbered object balls. The object balls are clearly and highly visibly numbered 1 through 15.
Each object ball has its number printed twice, opposite each other, one of the two
numbers upside down, black on a white round background.
The object balls numbered 1 through 8 have solid colors as follows:
1=yellow
2=blue
3=red
4=purple
5=orange,
6=green
7=maroon
8=black.
The object balls numbered 9 through 15 are white with
a centered band of color as follows:
9=yellow
10=blue
11=red
12=purple
13=orange,
14=green
15=maroon. The two printed numbers 6 and 9 are underscored.