Gun breech

Welin Screw. A type of gun-breech screw which has the surface divided into a number of segments which are struck with varying radii. The number of plain segments is less than half the total number, varying from one-third to one-quarter. Thus, the screw can be entered into the breech and locked by a fraction of a turn which corresponds to the number of segments eg, the Brit 6-inch Gun Mk 7 screw had four threaded and two plain segments, and it was locked in place with one-sixth of a turn... 

The terms nipple, cone and tube are applied in rather an indiscriminate manner to that poHion of a gun breech on which Iho copper cap containing the fulminate designed for firing the arm is placed. To be good and serviceable, the nipple should be made of steel, and carefully tempered but many are made of a low grade of steel, of common iron, and even malleable iron has been used, and case-hardened to render them fit for use. 

The Prussian Needle Gun, Breech Loader. Eifliag 4 grooves, one turn in 40 inches. 

The Whitney Anns Ca s Guns, Breech Lo ng comprising the Whitney, Kennedy, and Phcenix systems. Rifling grooves, ono turn in S3 incbea. Lands and grooves of equal width. 

It is best to examine what happened during this explosion by learning about the gun operations in the turret and the duties of the turret crew during a 16-inch gun firing. Figure 7.3 shows a projectile and propellant bag. Figure 7.4 represents the projectile and propellant bags as loaded into the gun breech. 

The projectiles (Figure 7.3) launched from a battleship can weigh up to 2,700 pounds and hit shore-based targets over 20 miles away with pinpoint accuracy, able to penetrate 30 feet of reinforced concrete and leaving craters 50 feet wide and 20 feet deep. The normal propellant/projectile combination (Figure 7.4) is six bags of propellant, weighing about 110 pounds each, loaded behind the projectile into the gun breech by a hydraulic mechanism known as the Rammer. ... 

Figure 7.5 shows a cutaway diagram of a 16-inch gun turret. The gun house is the visible portion of the turret above the deck of the ship and behind the gun barrels. The gun breech, into which the Rammer loads first the projectile and then the propellant bags into the breech, is shown to the right of the guns. Below the gun house is the electrical deck, where the mechanisms that rotate the turret and control the elevation of the guns are located. Projectiles are stored and moved to the gun house below the electrical deck on the projectile decks. 

Cradle Operator The Cradle Operator operates the hydraulic device behind the breech that positions projectiles and propellant bags to be placed on spanning trays and inserted into the gun breech by operation of the Rammer mechanism. This role was filled by Gunners Mate Third Class Richard Lawrence, age 29. 

Machine Gun. Automatic weapons which fire small arms ammunition. They are heavier than automatic rifles and are usually provided with a fized mount, such as a tripod, or wheels and a trail. These sustain the force of recoil and provide the means by which the gun may be positioned in the direction of fire. Machine guns utilize the discharging gas, or mechanical recoil of the gun to load, eject the cartridge, lock and unlock the breech. They are fed from either a belt, clip or magazine, and are cooled by either... 

Obturation. A process that seals the breech of a gun and prevents the escape of propint gases at the time of firing. In all modem firearms, light and medium artillen7, it is effected by the momentary expansion of the brass or copper cartridge case... 

Cannone ad anima liscia — Smoothbored Cannon Cannone ad avancarica - Muzzle-loading Gun Cannone antiaerea - Antiaircraft Gun 1 Cannone anticarro - Antitank Gun Cannone a retrocarica — Breech-loading Cannon Cannone a tiro rapido - Rapid-fire Gun... 

Jacket. A cylinder of steel covering strengthening the breech end of a gun or howitzer tube. It also refers to the water jacket on some machine guns... 

Field-Proof Gun. A special shot gun for taking simultaneously the recoil and pressures at 1 inch and 6 inches from the breech. The velocity and pattern can also be taken at the same time. The gun weighs 50 lbs and is suspended 5 ft below the supports it is fired by means of a pneumatic bulb in order not to disturb the gun. The gpn and support are shown in Fig F2... 

Gases may escape from the barrel through the breech end after the breech block has been opened. They may be toxic to the gun detachment if the breech end is situated in a confined space (naval gun turret, concrete pillbox, tank etc.). A flow of air to remove them is therefore essential. Similar hazards arise due to backflash. 

With the use of Gudol proplnt, the breech as well as muzzle flash were practically fill-minated and so was the smoke. The erosion of gun barrel was very low (Refs 1, 2 3 and Ref 4, p Ger 81)... 

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