Rolls
Rolls
   
It is better to stow drums, barrels, kegs, etc. vertically next to each other. Unless they are especially designed to fit together, you should use some type of separation material (eg. planks or plywood) between each row. Secure the cargo at the door end with braces against the corner fittings of the container.

Wooden barrels are not designed to withstand pressure around the middle. When stowed horizontally they should be supported on the ends by lath strips or blocks that keep the middle of the barrel above the floor of the container. Insert wedges to prevent rolling.