I have been making camp kettles. 

There are three styles that have been excavated.  The major difference is the handle attachment. The Ft. Meigs bail was just pierced trhough the side of the bucket. The Louisburg  Kettle had an ear attached with one rivet and the most common method was with two rivets.

The sizes are described as (smallest)to largest) 2 breadth, 2 1/2 breadth, 3 breadth, 2 lengths, 2 1/4 lengths.

The Army issued the camp kettles to the men for cooking.  They were designed to nest to save space.  Of course then the soldiers complained about carrying them when they were all blackened so linen sack were issued.