After the inspection was concluded, it was determined to expend "Baden" as a gunnery target. In January 1921 the first round of gunnery tests was ordered. The gunners at HMS "Excellent" fired the new armor-piercing (AP) shells that had been introduced after the Battle of Jutland. This round of tests was used to determine the most efficient ratio of explosives in the detonator caps; the shells fired at Jutland had a tendency to fragment when striking heavy armor rather than penetrate. The monitor moored some away from "Baden" to fire her guns from point-blank range. "Baden" was made to list to starboard by the removal of coal and armor from the port side, to simulate the effect of a shell striking armor from a plunging angle. The forward-most gun turret had by this time been removed. "Terror" fired 17 shells of various types into the ship. The Royal Navy concluded after these tests that the new shells were sufficiently powerful to penetrate heavy armor, and were much more effective than the previous versions that had been employed at Jutland. Following the tests, heavy seas caused the ship to sink in the shallow water; after three months she was again raised and docked for repairs. The ship was readied for a second round of testing by August 1921.