the housing with a bayonet joint that allowed for its replacement by destroyer tenders in the theater of operation, without dismantling the breech mechanism or other parts. Ballistics Maximum horizontal range with a projectile is . In the anti-aircraft role, the gun has a ceiling of at 85 degrees elevation. Armor penetration with special common shell 5.0" (127 mm) belt armor at 4.0" (102 mm) at 3.0" (76 mm) at 2.0" (51 mm) at 1.0" (25 mm) deck armor at with AA common shell: at Range with AAC Mark 49 (792 mps) 10° 15° 20° 25° 30° 35° 40° 45° AA Ceiling The new gun initial muzzle velocity is , and the gun life average initial muzzle velocity is about . US ships during World War II carried only small quantities of special common ammunition, as the anti-aircraft common was considered more useful, even if it meant achieving much less armor penetration. Bursting charges were explosive D composition A, the special common had only 0.9-1.2 kg due to its thicker walls (AP). Loading At the "LOAD" command, or if the mount is executing "RAPID" loading: (NOTE: Rapid loading means that, when the gun fires, the gun crew immediately reloads the gun without command until "CEASE FIRE" or "CHECK FIRE" is given.) The Powder-Man: Verifies that the RAMMER SPADE is at the rear of the "Rammer Tray" (see picture) Slips the "Butterfly" primer protector off the base of the powder case that is sticking knee high out of powder hoist on the deck. Throws the protector out of the mount. Pulls the powder case out of the hoist, and lifts it into the rammer tray. Verifies that the case is back against the rammer spade. Clears his arms from the tray. The Projectile-Man: Verifies that the powder case is in the rammer tray. Pulls the projectile out of the waist high projectile hoist. Places projectile in front of the powder case in the tray. Clears his arms from the tray. Pulls down on the RAMMER CONTROL (see RAMMER CONTROL at the upper left corner of picture). Rammer Load Cycle: Pulling down on the Rammer Control lever opens hydraulic valves inside the Rammer Controller. The opened valves port high pressure hydraulic fluid to the "Hydraulic Ram Cylinder" in the Slide behind the tray. The Ram Cylinder is connected to the "Rammer Cross Head". (The white horizontal bar behind the Spade in the