I made one for a rifle a couple years ago and matched the width up with the toe of the butt plate I made for the project. I made the inside cavity to hold a ball puller, breech scraper, and a cleaning jag. I made the box a couple times before I got the hinge to look like I wanted. To date, I have made two rifles with this type of toe plate box. I like it a bunch when I have it finished and the spring /latch assembly finished and installed. If I can find a photo I will attach it to this note.
Roger Sells