 Counter-battery fire again failed due to the inaccuracy of the worn-out guns and also because the army still lacked accurate means of locating enemy guns, as air observation and reporting and use of radio was only beginning.The inaccuracy through wear and the relatively light shell diminished their usefulness in the developing trench warfare, and they were replaced by the modern 60-pounder guns as they became available.At the Battle of the Somme in June–July 1916, there were 32 guns and 128 60-pounders engaged.