~Ian: As far as I know, these were the only gray grain hoppers the BN had, at least in the early years. These were built for the GN, with aluminum sides, and very quickly weathered to a non-metallic gray. I don't know whether the BN cars were painted gray, or if they stripped the GN lettering and relettered the bare aluminum. I suspect they repainted the cars, though, as I don't remember seeing a shiny aluminum BN car.
Gray was common on BN's smaller covered hoppers, and it looks like the same shade of gray.
As for what they carried, I suspect mostly grain, as that's what the GN bought them for. But the GN also hauled other stuff in them, so they could be used for anything with a density similar to grain, that wouldn't contaminate the car.
Years ago I made my own rosters for the BN and predecessor roads by copying a big pile of hump lists from June, 1973. By hand, in pencil. Those lists showed both the GN and BN cars, but apparently not what the were hauling, as that column is blank in my rosters. Other cars around them show various grains, so I assume these were mostly grain cars.
If I'd had a computer like today's, I could have digitized the entire lists with less work, in a spreadsheet program, and had every car that went over the Pasco hump that month. THAT would have been quite a resource!
