An externally adjustable pressure regulator includes a body having a shoulder, a longitudinal axis and a high pressure inlet. The body has an opening along a side. A bonnet has a regulated pressure outlet and is engaged with the body. A piston is positioned in part in the body and the bonnet. The piston has a shoulder, a longitudinal bore and a transverse bore at about the end thereof in flow communication with the longitudinal bore. A spring is disposed on the piston. A wedging element is positioned in the opening in the body side and is in contact with the spring. An adjusting ring engages the wedging element to move it into the spring to increase compression of the spring and off of the spring to decrease compression. Increasing compression of the spring increases a spring force of the spring on the piston and decreasing compression of the spring decreases the spring force on the piston.