The powder bag weight that Jeff mentioned is correct. It took six 110Lb. bags behind each projectile. The guys in the photos are shown placing the bags on the elevator that takes them up to the gun. The elevator carries 3 bags, so they ram the projectile into the chamber, then ram 3 bags behind it, then ram the last 3 bags behind it. Normally the bags are stored in powder tanks, 3 bags per tank. The tanks are about 5 ft tall. The photos showing the projectiles and powder are inside the barbette. The barbette is a thick steel tube that extends straight down through multiple decks, into the belly of the ship. It is the structure that the gun turret rests on and is the diameter of the turret base, and it serves as an armored magazine for the powder and projectiles. The curved wall behind the projectiles on the left in the photos is the inside surface of the barbette. During WWII when the battleships carried huge numbers of 40mm bofors guns, there were spare barrels with their water jackets in place for the guns, stored all around the outside wall of the barbette. They would be held vertically in place, just like rifles in a circular rifle rack.