Pyrotechnics primers

Raibun (Enka) (Thunder Powder or Smoke and Fire) consisted of K chlorate 60 Arsenic Sulfide 40%. Lt gray to tan powder used in fuze and pyrotechnic primers. Comp with Bakufun (Ref 1, p 25 Ref 5, p 369, where its compn is erroneously given as K chlorate 60 Antimony sulfide 40%)... 

Pyrotechnic primer compositions are often used to ignite gun propellants. The primer emits a burst of flame when it is struck by a metal firing pin, igniting the gun propellant. These primer compositions are therefore very sensitive to initiation and are capable of generating heat and shock. In order to reduce the sensitivity during the manufacturing process, the composition is used in the paste form. Examples of pyrotechnic compositions used in primers are presented in Table 8.5. 

Modem Pyrotechnics (1961) was the first pyrotechnic primer and collection of up-to-date information in the English language—written mainly in order to help the newcomer to the field of military pyrotechnics. Judging from the many comments 1 have received, it served this purpose well. 

Pyrotechnic primer compositions are often used to ignite gun propellants. The primer emits a burst of flame when it is struck by a... 

Barium nitrate is prepared by reaction of BaCO and nitric acid, filtration and evaporative crystallization, or by dissolving sodium nitrate in a saturated solution of barium chloride, with subsequent precipitation of barium nitrate. The precipitate is centrifuged, washed, and dried. Barium nitrate is used in pyrotechnic green flares, tracer buUets, primers, and in detonators. These make use of its property of easy decomposition as well as its characteristic green flame. A small amount is used as a source of barium oxide in enamels. 

K picrate was used as early as 1869 in expls, such as poudres Designolles (K picrate + K nitrate + charcoal) and poudres Fontaine (K picrate + K chlorate). It has also been used in pyrotechnic whistle compns (Ref 8), proplnts such as Ballistite, and in some primer mixts, ie, K picrate, Pb picrate K chiorate (Ref 4)... 

The larger rifles such as the familiar military rifle use cartridges of the type shown in Fig. 19.3. The relatively heavy base contains centrally a pyrotechnic percussion igniter (cap) and also a rim on which the ejector mechanism operates. Bullets can be made of various materials, but the detailed construction depends on whether they are to be used for armour piercing, anti-personnel, incendiary or tracer purposes. In operation, the primer is fired by the striking pin of the rifle, the propellant ignites and the... 

Whenever the operation to be performed involves the potential to cause the initiation of the propellant, explosive or pyrotechnic (PEP) component(s) of a munition item, the APE is either operated by remote control, with the operator behind a protection wall or barrier, or it is enclosed in a protective barricade or operational shield. Barricades or operational shields are designed to protect personnel and assets from the effects of blast overpressures, thermal effects or fireball, and fragments result from the initiation of PEP components, such as the fuze, primer, propelling charge, burster, etc. 

Ignition means Method employed to ignite a deflagration train of explosions of pyrotechnic substances (e.g., a primer for propelling a charge, an igniter for a rocket motor, or an igniting fuse). 

Primers are used for the ignition of propellants and pyrotechnics. They are categorized as percussion primers, used mainly for the ignition of propellants, and stab primers, used in explosive trains of fuses and electric primers. 

Pyrotechnics are often used in the production of fireworks and primers. A pyrotechnic contains both a fuel and an oxidizer formulated to produce a lot of energy. The energy is then used to produce a flame or glow (matchstick) or combined with other volatile substances to produce smoke and light (fireworks) or large quantities of gas (firework rockets). 

Barium chromate is used as a pigment in paints, ceramics, coloring glasses, fuses, and porcelains as a corrosion inhibitor to prevent elecrochemical corrosion at the joints of dissimilar metals in safety matches in metal primers in ignition control devices in pyrotechnic compositions and as an initiator for explosives. 

The items used for military purposes include those used for small arms ammunition, artillery ammunition, rocket ammunition, aircraft bombs, land sea mines, grenades, demolition devices and pyrotechnic devices. As some items (such as detonators, primers, etc) can be used in several kinds of ammunition our write-up might contain some repetitions... 

Igniters, which include devices called squibs, lighters and firing devices, etc are used for initiating expl or pyrotechnic compns whose nature is such that it is desirable to use flame or flash for their initiation and not a shock as produced by primers or detonators. 

Low-Explosive (LE). An explosive which when used in its normal manner deflagrates or burns rather than detonates that is the rate of advance of the reaction zone into the unreacted material is less than the velocity of sound in the unreacted material. LE s include propellants, certain primer mixtures, BkPdr, blasting explosives (See Ref 44, p B202-L), pyrotechnic compositions and delay compositions. Whether an explosive reacts as a high explosive or a low explosive depends on the manner in which it is initiated and confined. For example, a double base propellant when initiated in the usual manner acts as a LE. However, this material can be made to detonate if it is initiated by an intense shock. Conversely, a HE like TNT, can, under certain conditions be ignited by flame and will burn without detonation (Ref 40a, p 97)... 

In addition to matches and other scratch sensitive materials, prime ignition of pyrotechnic and other ordnance items can be achieved by stab, percussion or electrically ignited primer (or squib)... 

Accdg to Ref 37, pp 3 6, the ignition ttain for pyrotechnics begins with an initiator. usually a primer which may be of the percussion, friction, or electric type. The flame produced on initiation is transmitted successive-... 

These primers can be used not only in small arms but also in some pyrotechnic devices and fuzes. All simple primers are small in size, 0.21 to 0.31 inch in diam and 0.12 to 0.23 inches long for rifle ammunition and slightly Smaller for carbines. They contain only one small charge of primary expl or a mixture which must have sufficient sensitivity to be initiated either by the crushing or stab action of a firing pin... 

Delays, Relays, Leads and Their Uses in Fuze Detonators, Fuze Primers and Some Pyrotechnic Items a) Definition of Terms... 

Fuze, Hand Grenade. A pyrotechnic delay fuze initiated by release of a lever which in turn permits a striker to impinge on a primer. The output of the fuze is designed to ignite or detonate a filler of a hand grenade... 

Ignition Compositions for Use With Pyrotechnics. This subject was treated in considerable detail in Vol 4 under Detonator, Igniters and Primers, Sect 3, Part B Ignition Train Used in Pyrotechnics, pp D759-768, with the following additional reference ... 

Ref Frankford Arsenal, "Primer, Pyrotechnics and Incendiary Compositions for Small Arms , Rev 2 (1954), p 43... 

In the initial stages, the end use of n-Al was largely dominated by defense-related applications. Small caliber primers for defense munitions, additives for solid and hybrid rocket propellants, enhanced lethality explosives and pyrotechnics and thermite-based weapons are some typical military applications of n-Al powder. The use of n-Al powder has also been reported for some civil applications such as fireworks, automotive inflators and airbag initiators as well as drilling and oil exploration. 

The burning of Al-WOx stoichiometric MICs is relatively easier compared with micron-size-based pyrotechnic formulations [97] and their open-tray burn velocity have been reported to be 250ms 1. Such MICs are likely to find applications in electric matches and gun primers. 

Dextrin also has been and is now used as a binder in various pyrotechnic compos (Ref 11) Davis (Ref 5, pp 62ff) gives numerous examples. As a binder a desensitizer it has been used in primer compns, as for example in a friction primer used for an airplane flare (Ref 5, p 454), or in a compn. for electric primers consisting of K chlorate 88, charcoal 10 dextrin 2% (Ref 9, p 118). As a fuel dextrin was used in some commercial expls, such as Nobelit "Fordit (Ref 2, p 407). In some gelatine expls, such as "Safety Jelly Dynamite (Ref, p 407), a paste called "glue-dextrine-glycerine jelly was used... 

Heat-producing pyrotechnic compositions are used in a variety of applications, for example, as first fires in pyrotechnic devices to ignite other materials, as primers, as heat generators in pyrotechnic heaters, as propellants in gas generators and rocket motors, and as incendiary devices. 

Pyrotechnic compositions which are used in primers or first fires are very sensitive to initiation, whereas compositions which are used in heat-generating devices are less sensitive. The sensitivity of the compositions can be controlled by reducing the amount of oxidizer and choosing a less sensitive oxidizer. 

---