In reenacting, the details count. One detail that seems to get the gloss-over are correctly made ammo boxes.
The Yellowhammer Rifles have an in-depth look at a .69 caliber box at the Civil War Maritime Museum in Columbus, GA. Another site has instructions for building ammunition packing boxes.
Charlie's Boatworks is an interesting site, even though he's not an official 'favorite' sutler. He sells ammo and hardtack boxes with the correct specs and materials. These have the correct stenciling and box color for the type caliber. It would be nice if he'd do a box for blanks, too.