There were many, many firms in Bradford either directly or indirectly involved in the manufacture of munitions, from making picric acid to making the shell casings, from making silk linings to filling the shells. Below is a list of just a few of them who are mentioned within Great War Britain: Bradford.

Heckmondwike - Henry Ellison Ltd picric acid makers - explosion Dec 1914
Low Moor Munitions Factory - Picric acid makers - explosion Aug 1916

Phoenix Dynamo Munitions factory - Shell factory, output from spring 1916 - Royal visit by King and Queen May 1918
National Shell Factory: Bradford - Valley Dyeworks site, output from Nov 1915

Listers Mill - silk shell linings