Bullet jackets

Pallottola a revestimento d acciao — Steel-jacketed Bullet... 

Jacket, Bullet. A metal shell surrounding a metal core, the combination comprising a bullet for small arms. The jacket is either composed of, or coated with, a relatively soft metal, such as gilding metal, which engages the rifling in the bore, causing rotation of the bullet Ref OrdTechTerm (1962), p 168-L... 

Italian 6.5mm expl cartridge of WWI could be recognized by an unusual shape of cupronickel-jacketed bullet (Fig 10 of Ref)... 

Japanese Army 7.7mm, semi-rimmed expl round with flat-nosed, gilding-metal jacketed bullet is shown in Fig 12 of Ref... 

Imperial Russian 7.62mm expl round for rifles and machine guns had a cupronickel jacketed bullet with flat nose. It contd the expl, detonator and firing pin (Fig 14 of Ref)... 

The self-loading pistol became possible because of the development in ammo. The production of a strong case, capable of producing total obscuration as well as withstanding not only proplnt pressure but the stress of extraction, was the first requirement. Next came the production of propints able to burn away completely in the first inch or so of bullet travel and lastly the jacketted bullet, firmly crimped into a brass case, which could withstand the shock of loading... 

The Sintox primer mixture contains tetracene, diazole, zinc peroxide/ titanium powder, and nitrocellulose ball powder.53 The use of this primer coupled with a totally jacketed bullet (base also enclosed) entirely eliminates the health hazard problem. 

In the majority of bullets the lead base is exposed to the hot propellant gases. This applies to unjacketed and jacketed bullets (excluding total metal jacketed bullets). Some bullets incorporate a gas check in the base to prevent erosion by the hot gases. Such erosion can upset the symmetry of the bullet and consequently the accuracy. The base of the bullet maybe filled or covered with a substance, for example, Alox base lubricant, that is unaffected by the... 

The bullet jacket material is almost always harder than the bullet core material, with the one exception of armor-piercing bullet jackets. Bullet jacketing is done either by electroplating or, much more commonly, the jacket is manufactured separately from the bullet, and the bullet then forced into the jacket in a press. Another method is to pour molten lead into the jacket. The edges of the jacket are usually partly rolled over the base of the bullet or attached by some other physical means. 

Whenever a jacketed bullet strikes a target it is possible for the core and jacket to separate, with a consequent reduction in penetration. To prevent such an occurrence a variety of crimps, folds, jacket geometries, and melted core techniques are employed. Another method of interest to hand loaders is the use of a product called Core-Bond which is a flux that removes surface oxides allowing molten lead to bond directly to the jacket. This allows a degree of alloying between the two metals, which is claimed to provide bonding superior to that achieved by physical methods. Soldering of the jacket to the core has also been employed.65... 

Sometimes a combination of bullet core materials is used to produce a hardness difference between the base and the nose (dual core bullets), for example, jacketed bullets with a lead nose and a steel base, a steel nose and a lead base, or a soft lead nose and a hardened lead base. 

Some jacketed bullets incorporate a small cavity in the nose which is filled with a material different from the bullet core. In some bullets the cavity... 

Another German design was a jacketed bullet with a hollow in the nose. On impact the steel plug squashed the glass ampoule against the lead core, causing the fluid to pour out of the nose cavity. This is illustrated in Figure 11.13. 

Detectable FDR is mostly particulate in nature. Unjacketed lead bullets produce residue in which greater than 70% of the particles are lead. Coated bullets give the same result, except that a substantial proportion of the lead particles contain copper from the coating material. With jacketed or semi-jacketed bullets the proportion of lead particles in the residue is greatly reduced. It was concluded that most of the lead in the residue comes from the bullet rather than from the primer. This has subsequently been confirmed by experiments involving the use of radioactive tracers.172... 

Type of ammunition—Jacketed bullets produce substantially fewer FDR particles than unjacketed bullets. Primer type (size, composition, burning characteristics) can influence the number of primer particles produced. The temperature and pressure achieved by the burning of the propellant determines the power and velocity of the bullet which can influence the number of particles deposited. 

Note Examination of the copper and zinc relationship revealed that for the unjacketed bullet, 94% of the particles contained copper only and 6% contained both copper and zinc, with copper > zinc. For the jacketed bullet, 90% of the particles contained copper only and 10% contained both copper and zinc, with copper > zinc in 9.5% and copper = zinc in 0.5%. 

A test was conducted to determine the weight loss of some bullets after discharge. Results are given in Table 20.3. From the limited experimental data it would appear that, as expected, the full metal jacketed bullets lose less than the soft unjacketed bullets. The FMJ bullet with its base enclosed lost less than its equivalent with its base exposed. This is also predictable as the exposed base is subject to erosion during discharge. The. 38 SPL + P unjacketed bullet... 

Only one of the two nickel-jacketed bullets, number 43, gave nickel on the perimeter of the bullet hole. Nickel was frequently detected from nonnickel-coated bullets. This is a surprising result which demonstrates that the presence of nickel cannot be used to identify the use of a nickel-jacketed bullet. The origin of the nickel is unknown but it may have originated from the primer cup coating. 

Analysis of the nny 82 ammunition as previously detailed shows that it uses a mercuric corrosive primer. Analysis of the Chinese 351/73 ammunition revealed that it has a copper-coated iron-jacketed bullet with an iron core and a lead tip, the cartridge case is steel with a brown colored lacquered finish, a brass primer cup, and the propellant is single based with DPA, 2 x nitrodiphenylamines, camphor, and contains no inorganic additives, and the discharged primer composition is antimony, potassium, chlorine, mercury, tin, sulfur, iron, manganese, phosphorus, zinc, and lead in descending order (lead, antimony, mercury type). 

The next stage in the development of environmentally friendly ammunition was when Geco produced ammunition with a totally jacketed bullet (TMJ) and a primer composition containing much reduced lead, antimony,... 

SWC bullet semi-wad-cutter bullet T bullet tracer bullet TMJ bullet total metal-jacketed bullet Win Winchester... 

Bench press equipment can make Jacketed bullets and change cartridge cases from one caliber to a nother. A 30-Ob case can be made into 21 other different military and commercial cartridges. Bench equipment Is 5 10 times faster at reloading than Lee Loaders. 

---