USGA Rules on Golf Ball
General
Appendix III is divided into the following five
categories:
-
Weight
-
Size
-
Spherical Symmetry
-
Initial Velocity
-
Overall Distance Standard
The rules on the golf ball are precise and numerical in
comparison to the more descriptive rules that relate to
clubs. All of the specifications listed below are tested
and checked under laboratory conditions, both indoors
and outdoors. These specifications are discussed briefly
below.
1. Weight
Appendix III, 1 states that a ball must not weigh more
than 1.620 ounces avoirdupois (45.93gm). This is one of
the simpler tests, as all that is required is an
accurate set of scales. There is no minimum weight, thus
a ball can be as light as the manufacturer desires.
2. Size
The ball must have a diameter of not less than 1.680
inches (42.67mm). The instrument used to measure size is
a metal ring gauge. Full details of the test
specification are available from the USGA.
It is important to note that there is no maximum size,
the ball can be as large as desired provided its weight
does not exceed 1.620 ounces (see The Ball, Section 1).
3. Spherical Symmetry
The intent of this rule is simply to ensure that a ball
is designed and manufactured to behave as though it is
symmetrical. Full details of the test specification are
available from the USGA.
4. Initial Velocity
There is a formal test procedure carried out on
equipment approved by the USGA to check that golf balls
meet the Initial Velocity specification. The intent of
the rule is to limit the speed of the ball off the
clubface. Full details of the test specification are
available from the USGA.
5. Overall Distance Standard
This rule was first introduced in 1976 in order to
restrict the overall distance (carry and roll) that a
ball can travel under specific conditions. Full details
of the test specification are available from the USGA.