On the run up to the war, new official munitions factories were created, off shoots of the Royal Arsenal in Woolwich. These were the Royal Ordnance Factories (ROF). When war broke out, many textile mills were converted to make munitions and some old mills were reopened.
The three processes of making shells, producing explosive chemicals and then filling and priming the shells ready for use were all kept separate. Factories would specialize in one of these three procedures.
The shell casings were often made in cotton mills or iron foundaries, for example Bulloughs of Accrington and S.S. Stott Ltd of Haslingden. The chemicals used for the explosives could be made by companies such as ICI’s Nobel Explosives. The explosives sites were obviously placed away from areas of high population density, but would need a good railway link.
The dangerous work of filling the shells with the explosives and priming them so that they were ready for use was done at the Royal Ordnance Factories. The site of ROF Chorley was the biggest munitions filling site in the country and was dubbed ‘Filling Factory No.1’. Other filing sites were ROF Risley (Filling Factory No.6) and ROF Kirkby (Filling Factory No.7). Kirkby had two major accidents during its war years, and in both instances civilian workers at the site were killed.
Other ROF sites in the Lancashire specialized in different areas of armaments. ROF Blackburn (Lower Darwen) was nicknamed the ‘Fuse’ or ‘Fuze’ because the fuse mechanism for explosives were manufactured there. The factory opened in 1937 and its site in Blackburn was thought to be less likely a target than those in the south and east of the country. It was never hit by bombs, but the Luftwaffe did have detailed aerial photographs of it, so like much of the north west, it was clearly a target. In recognition of its work, the King George VI and Queen Elizabeth visited in 1941.
Not all ROF were used to make large scale weapons. For example, ROF Fazarkeley produced Lee Enfield rifles and Sten and Sterling submachine guns.
Lancashire 1939-1945: The Secret War, Ron Freethy, 2005, Countryside Books
Lancashire 1939-1945: Working for Victory, Ron Freethy, 2007, Countryside Books
East Lancashire at War, Nick Dunnachie, 1995, Alan Sutton Publishing Limited
Individual pages on ROF Sites: