Abstract: A method and apparatus for determining: (1) the location of a weight block in a previously undrilled bowling ball; (2) locating thumb and finger grip holes and determining a depth for each hole on a previously undrilled bowling ball such that the bowling ball conforms to the bowler's balance specifications; (3) the same as in (2) above except that the location of the thumb and finger grip holes and depth of the holes are drilled in order that the bowling ball will be dynamically balanced; (4) locating a balance hole and determining the depth of the balance hole on a previously drilled bowling ball such that the bowling ball conforms to the bowler's balance specifications; and (5) the same as in (4) except that the location of the balance hole and the depth of the balance hole are drilled in order that the bowling ball will be dynamically balanced.