A system for externally testing a pipe joint connection utilizes a well known oil field apparatus with minor modifications to perform an important test of the hydraulic integrity of the pipe joint. A pair of hydraulically operated blowout preventor rams are connected by means of a pipe of sufficient length to accommodate the enclosure of a pipe joint connection. The connecting pipe forming the enclosure is aligned with the pipe opening in the rams. Thus the assembly is comprised of upper and lower rams with a pipe therebetween forming a test chamber. The lower rams are inverted so that the rams are closed, the connecting pipe forms a sealed chamber. A port is provided in the connecting pipe to permit fluid under pressure to be passed into the chamber when the rams are closed about pipe being tested. The test assembly is connected by a flange below the lower ram to the wellhead. As a string of pipe is passed into the well, the pipe joint connections are positioned in the chamber, the rams are closed, and fluid pressure is applied externally to the pipe joint. Measurement of fluid pressure decay determines if a leak exists.