BUR #9754 has been rejected.
mass update bullet_casing -> shell_casing
nuke bullet_casing
deprecate bullet_casing
When bullet_casings was aliased with shell_casing, we missed the singular bullet_casing tag. There are 16 images with the tag, so its not a commonly used one, but I think we should clean this one up before more people (myself included) accidentally misuse the tag.