Why are cartridges made of brass




















Cups are very stout, and are a little wider than they are deep. Notice the ridges on top of the cup. As the cup is drawn into a casing, these ridges become more pronounced. This is what a cup looks like after passing through the first of three draw presses. The cup is now a little taller, and considerably narrower. The cup then has to be annealed, or heated, to relax the grain structure of the metal enough to continue elongation.

The casing also has to be washed prior to being put through the next draw process. The cup has now passed through the second of three draw presses. The cup is now much deeper than it is wide, and is starting to look like a close-ended tube.

As with the first draw, the cup will need to be annealed and cleaned again prior to further elongation. The cup has now reached its total elongated length, and is now considered a casing. Notice how uneven the top of the casing is. This is partially due to the grain structure in the side walls of the cup, as well as cup side wall thickness variations.

It should be noted that it is not usual to see a casing in this form, as it would have been pinch trimmed prior to exiting the third draw press. Here we have displayed the ring of brass trimmed off the top of the tube in the last step.

The tube also has to be washed prior to being advanced onto the next step of the forming process. Notify me of new comments via email. Notify me of new posts via email. February 9, June 7, Jessica M. Brass casings have their pros and cons for cartridges: Brass is Reusable: A key reason that brass is preferred is its reusability.

Ask any gun owner or hunter, and the most common reason is because it can be reloaded. Many people retrieve and reload their brass casings because it beats the price of new cartridges.

In fact, most gun shops and fellow shooters are always willing to buy any used brass shells from gun owners. If you reload your own ammunition, the brass casing is the most expensive item in the process. Brass is Reliable: Even though brass is flexible, it is very reliable. With that being said, it is less likely to get stuck or impinged in the firearm as compared to aluminum or steel cased cartridges. For those shooting hundreds of rounds, brass has withstood the test of reliability. Another key feature is the softness of the metal itself.

This mechanism makes it possible to load from the rear of the barrel breech-loading. They also ensure that the cartridge explodes forward, protecting the user from any explosions. When the firing pin strikes the primer, it explodes, igniting the gunpowder or cordite.

The gunpowder burns slowly, accumulating gases and pressure to thrust the bullet out of the cartridge. The casings, which retain most of the heat after this process, will have to be ejected manually or automatically. This process cools the gun faster since they take away most of the heat. This feature also helps slow down the wear and tear of the guns. There have been attempts to create caseless ammo, but we are a long way from that. Even though caseless ammo may be lighter and cheaper to produce, they are hazardous due to temperature sensitivity and the inability to seal the chamber when firing.

The four parts of a cartridge are composed of different materials;. Brass is more robust and can expand and contract without cracking. Brass cases were relatively easy to manufacture and a well-established brass industry stood ready to supply the essential alloy for the purpose. The manufacturers of steel cases was not altogether new in , but it was nearly so.

A few steel cases for artillery ammunition had been made in the United States and Germany during World War I, but the results had not been altogether successful in either country. Because of the abundant supply of copper and zinc available in the United States, and the many difficulties inherent in the use of steel cases, little attention was paid to the matter in the years between the wars.

In and a few cases made of seamless steel tubing were submitted to the Ordnance Department by commercial producers for test but none proved satisfactory. As a result, when Ordnance engineers and representatives of industry were suddenly faced in with the problem of manufacturing steel cases they had to begin virtually from scratch. The problems involved seemed at first to be insurmountable. It was, of course, essential that the steel case be just as effective as the brass.

No substitution that impaired the performance of ammunition could even be considered. Further, the steel case had to be perfectly interchangeable with the brass case in order to simplify its use on the battlefield. To achieve these results, it was necessary to develop a new type of steel with the elasticity required of cartridge cases -- and to do it without using appreciable quantities of scarce alloying elements or scarce heat-treating equipment.

New techniques for deep-drawing steel had to be devised and tested, and a protective coating had to be developed for application to the finished case to prevent corrosion. Following the solution of these and other design problems it was necessary to devise manufacturing processes that would make the substitution of steel for brass feasible in terms of cost, machine tools, and manpower, and also in terms of volume production running into millions of rounds per month.

Finally, it was highly desirable, if not actually mandatory, that the manufacturing techniques be of such a nature that the facilities already engaged in the manufacture of brass cases could be used, with a minimum of readjustment, to produce steel cases Small Arms Cases The development of steel small arms cases was carried on concurrently with the [partly successful] development of steel artillery cases, but, with the exception of one caliber, proceeded slowly.

Because of the extremely high pressures generated in small arms cartridges, the substitution of steel for brass posed more difficulty than it did in artillery cases. At the outset of the project a broad division of labor between government and industry was agreed upon: development of commercial types of ammunition, such as shot-gun shells and the.



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