 Agamemnon also was used to test the vulnerability of battleships to 6 @-@ inch ( 152 @-@ mm ) , 5 @.@ 5 @-@ inch ( 140 @-@ mm ) , and 4 @.@ 7 @-@ inch ( 120 @-@ mm ) rounds fired at her by ships such as the battlecruisers Renown and Repulse while she maneuvered under radio control . These tests showed that ships protected as well as Agamemnon , such as the later dreadnoughts , would suffer damage to their upper works if struck by such shells , but would not have their steaming or fighting capability seriously impaired even by numerous smaller @-@ caliber hits . 
