Gun barrel

Germany, the United Kingdom, and the United States shared ahke in the early development of stainless steels. In the United Kingdom in 1912, during the search for steel that would resist fouling in gun barrels, a corrosion-resistant composition containing 12.8% chromium and 0.24% carbon was reported. It was suggested that this composition be used for cutiery. In fact, the composition of AISI Type 420 steel (12—14% chromium, 0.15% carbon) is similar to that of the first corrosion-resistant steel. 

The Majac jet pulverizer (Ho.sokawa Micron Powder Sy.stems Div.) is an opposed-jet type with a mechanical classifier (Fig. 20-55). Fineness is controlled primarily by the classifier speed and the amount of fan air dehvered to the classifier, but other effects can be achieved by variation of nozzle pressure, distance between the muzzles of the gun barrels, and position of the classifier disk. These pulverizers are available in 30 sizes, operated on quantities of compressed air ranging from approximately 0.6 to 13.0 mVmin (20 to 4500 ftV min). In most apphcations, the economics of the use of this type of jet pulverizer becomes attractive in the range of 98 percent through 200 mesh or finer. 

Balance. If the center of mass of the projectile is not located extremely close to its longitudinal centerline, the center of pressure can form a couple with the inertial reaction through the center of mass, making the projectile tend to tumble in the barrel (Barker, 1985). Tumbling is prevented by the gun barrel, which exerts counteracting asymmetric forces on the projectile during its acceleration. These forces can lead to asymmetric wear of the projectile. If the center of mass is closer to one end of the projectile, which it nearly always is, the situation is unstable the wear increases the imbalance, which increases... 

Gouging. Whenever a velocity over about 1.6 km/s is anticipated, the projectile must be designed to prevent any contact of metal projectile components with the gun barrel. Only plastic components of the projectile should touch the barrel. Metal sliding against metal at velocities over 1.6 km/s can result in serious or even disastrous gouging of the gun barrel in a single shot (Barker et al., 1989). 

Flinte,/. (shot)gun (formerly) musket. Flinten lauf, m. gun barrel, -achrot, n. gunshot, small shot. 

Lauf, m. course, path, track running, run, race flow current circulation passage (gun) barrel, -bahn, /. track, runway, run orbit career racecourse. 

Rumford decided to try a more controlled experiment. He placed a brass gun barrel in a wooden box containing about nineteen pounds of cold water, and used a team of horses to rotate a blunt steel borer inside the barrel. After 2.5 hours, the water boiled As Rumford described it, It would be difficult to describe the surprise and astonishment expressed on the countenances of the bystanders on seeing so large a quantity of cold water heated, and actually made to boil, without any fire. ... 

Mayevskii, N.V. (1823—1892), eminent Russian ballistician and originator of the science of Exterior Ballistics. He was equally known for work in the field of Interior Ballistics. In 1856 he designed a method of measuring the pressures in various sections of a gun barrel on firing. In 1867 he conducted expts to detn projectile velocity and correlated press with velocity Refs 1) Hayes, Elements of Ordnance , J. Wiley, NY, 437 (1938) 2) A.D. Blinov, Kurs-... 

Muzzle Brake. (Freins de bouche in Fr, M lin-dungsbremse in Ger). A cylindrical device with flanged or baffled surfaces which is attached to the muzzle of a gun, usually by threads, to offset a long or complete recoil of the gun when fired. The expanding proplnt gases strike the baffles, thus pushing the gun barrel forward. This action can shorten the actual recoil distance, or it may relieve an overloaded recoil system. The latter would occur when a conventional gun was deliberately overloaded to increase the projectile velocity... 

NACO (Navy Cool). A type of proplnt developed by the US Naval Ordnance Station, Indian Head, Md. It burns at temps 300° cooler than standard proplnts, thereby reducing gun-barrel wear by more than 50 percent (Ref 3). 

The formulation for use in the Swedish Army rifle contained Guncotton 96.2, sol cotton 1.8, resin, a stabilizer and other materials 2.0%. These propints were very stable, nearly hygroscopic, and produced much lower temps than corresponding double-base powders such as Cordite, Ballis-tite, etc. As a result, gun barrel life was lengthened... 

Or gen Gun. A piece of ordnance with numerous gun barrels arranged side by side and capable of being fired simultaneously. In the fourteenth to the seventeenth century as many as 160 barrels were sometimes so arranged. Also see under Orgues... 

Chamber Pressure. The pressure existant within the gun barrel at any time as a result of the burning of the proplnt charge. This pressure... 

Except for special application, especially primers intended for use in high-temp environments, K. chlorate priming mixts have been abandoned. The main reason for this change is that K chlorate primers are corrosive. After firing, hygroscopic K chloride, resulting from the decompn of the K chlorate, is deposited in the gun barrel. This causes immediate and extensive rusting of the barrel... 

One of the earliest uses of SP, and a use that continues to be important even at present, was in propelling projectiles out of gun barrels. The 1 heat and combustion products of the propelling SP charge can have a deleterious effect on the bore of a gun barrel. This breaking down and wearing away of bore metal is called erosion. Gun barrel erosion has been discussed at some length in Vol 5, El 12—20 and D1536... 

Since the publication of these articles no major breakthroughs in erosion, or rather erosion prevention, have been made. However, several patents claiming methods and means of minimizing gun barrel erosion have appeared recently. These are abstracted below ... 

A variant of gun barrel erosion, namely rocket nozzle erosion, is discussed in the following abstract ... 

In the extruder the flour and water will be subjected to intense agitation and will be heated to above 100°C under pressure. Extruders are constructed to work at elevated pressures, indeed the barrel of the extruder is constructed in the same way as a gun barrel. Under these conditions the starch will gelatinise but the water cannot boil because the high pressure elevates the boiling point. 

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