The angle between two holes on a Pitch Circle Diameter

Calculate the angle between two holes or patterns of holes lying on an imaginary circumference of a bolt circle or pitch circle diameter (PCD) with a known diameter. Although this GD&T method is older, you may still stumble upon these drawings. The value x is the shortest distance between two holes that can be measured with a caliper using the external jaws. The value of x will be the same regardless of the chamfer size around the holes.