A manually actuated dispensing gun can deliver different fluids to be mixed. The gun has a body assembly with first and second valves. A lever arm manually actuates the valves. A cap has first and second fluid inlets that are coupled to respective controlled fluid outlets of the valves. The cap has a duct that opens into and runs from a first inlet to a first cap outlet, and another duct that opens into and runs from the second inlet to a second cap outlet without opening into the other duct. One of the ducts has a larger cross-section flow area along its entire length than the other. Other embodiments are also described and claimed.