During the Confederacy of Independent Systems's occupation of the planet Ryloth, the tactical droid designated TX-20, along with his contingent of battle droids, established a defensive line consisting of five of these proton cannons within the city of Nabat. When the Grand Army of the Republic initiated a landing operation, the cannons successfully destroyed one of the three assault ships. Subsequently, Jedi General Obi-Wan Kenobi commandeered one of the cannons and used it to destroy the remaining cannons. In the Second Battle of Geonosis, these weapons were employed to impede the progress of Republic forces attempting to reach the primary droid foundry. A proton cannon targeting Republic ships during the landing phase was neutralized by BTL-B Y-wing starfighter/bombers. Following the establishment of ground forces at Point Rain, Jedi General Anakin Skywalker led his Padawan, Jedi Commander Ahsoka Tano, and a contingent of clone troopers into the heart of the enemy's defenses. They utilized Electro Magnetic Pulse grenades to disable the scanners on the proton cannons. This action enabled All Terrain Tactical Enforcers to advance unimpeded and eliminate the Geonosian defensive structures, encompassing both the proton cannons and the shield generator. The cannons also saw action at the Battle of Anaxes, where numerous units defended the Anaxes assembly complex.

The J-1 proton cannon made its initial appearance in the introductory newsreel of the The Clone Wars: Season One episode titled "Innocents of Ryloth." Subsequently, they were featured in the unfinished story reel of the episode "Unfinished Business," as well as the completed adaptation that aired on Disney+.