Abstract: The dispenser provides for accurate and easily repeatable dispensation of selected volumes of paint colorant. The dispenser has an adjustable stop for limiting the travel of a piston in a paint colorant metering pump. The stop position can be adjusted in equally spaced increments by a coarse adjustment which includes a pin which may be engaged in equally spaced holes in a stop support member. The stop position can be adjusted to intermediate positions by a fine adjustment. The fine adjustment includes a threaded stop member mounted in a threaded aperture. The pitch of the threads on the stop member is such that the stop moves a distance of one increment in a single rotation of the stop member. The stop member may be turned by a knob. The knob is slidably mounted so that it does not move axially with the stop member and has a limited rotation so that each position of the knob corresponds to only one stop position.