Thanks for the super detail photos, Leo!
This is the only original Creedmoor box that extactly matches the period catalog cuts from the 1870's. There may be surviving examples in other collections but none have been made public before.
Measurements are- Closed, 12.75 X 8 X 4.75". Catalog cut from Homer Fisher's 1880 issue. Cost was $6.00, a very expensive shooting box!