US Charge, Spotting, M39A1
The M39A1 is authorized for use with the 250 pound practice bomb, M124. It contains a charge of approximately 10.20 pounds of 80% black powder and 20% flaked aluminum powder in a cylindrical terne-plate casing. A cover assembly consists of a funnel-shaped front cover (closing the forward end of the casing), a tube extending nearly through the center of the charge, and a tube guide which supports the tube. The container is closed at the rear by a felt pad and rear cover.
Collaborative Ordnance Data Repository