The gun course is a facility located in the Port, featured in Jak II and Jak 3. It contains a firing range which Jak used numerous times to strengthen his Morph Gun abilities and test new weapons. Tess also used this building to develop new weapons for the war effort.
In both games the gun course featured a range in which automatic wooden targets would pop out of ground railings for a limited time, each awarding more points the quicker they are shot. Most were default targets, averaging about 100 points, however some bonus targets appeared that were gold in color and averaged around 250 points (Jak II) and 450 points (Jak 3). There were also "friendly" targets, commonly depicting civilians, which subtracted 100 points if they were shot.
During Jak II, the targets resembled metal heads and were harmless. In Jak 3, the targets changed to resemble KG death bots, with some being harmful; using turrets to aim at Jak, as well as some being explosive.
There were multiple course layouts specialized for certain weapons, such as the Scatter Gun course and Blaster course during Jak II, and the Gyro Burster course and Plasmite RPG course in Jak 3. The range also came with unlockable courses for other weapons, as well as a Ratchet gun course and a Clank gun course.