BR had a single batch of 50 of these GWR design 'Herring' ballast hopper wagons built in 1951. Being vacuum braked and of low payload they were popular until the mid 1980s. They worked on the LMR, ER and ScR.
Guestbook for BR (GWR design) Herring ballast hopper ZLV
Ian Nash(non-registered)
I think the "Herring" was what we in the Reading Relaying Gang called "Knock Ups" owing to the way the ballast was released. Quite dangerous by modern standards. We also used "DogFish" but were very difficult to open as the wheels jambed up