105mm shells separate into the brass and the projectile; the brass having the primer and powder bags and the projectile being the explosive shell and fuse. The open top of the brass is covered with plastic and taped into place in this picture, to protect the powder from the air. These projectiles have already been fused and are ready to fire. The FDC firing orders tell the gun crew how many of the 7 powder bags to use; the rest are removed and the projectile butt inserted into the brass case. These bad boys are now ready to fire unless the fuse needs a time setting, which takes but a moment. FDC instructions included the fuse type and any time settings.