Electric Primer

Dynamite primers with LEDC (low energy detonating cord) delay assemblies made by the DuPont Co are described in Ref 50, pp 106-09 192-93. They are essentially nonelectric MS(microsecond) delay caps  

The LEDC produces very little noise on detonation and for this reason can be used in highly populated areas. It is usually recommended for operations where bottom-hole initiation is desired and electric blasting caps cannot be used for fear of prematute detona- 

The method of priming dynamite with Primacord ( detonating fuse ) is described in Ref 38, pp 72-3 and in Ref 50, pp 195-5)6 When this method is used it is 

Priming with Nitramon and Nitramex 3 primers is described m Ref 50, p 196-98. Since they are packed in metal containers, there is a potential hazard in loading them into a borehole following dynamite or other conventional expls. They are intended only for charges of blasting agents under most conditions. They are waterproof 

as well as Tovex and Pel-letol contain non-NG HE ingredients and for this reason are not true blasting agents but are similar to them because they are cap-insensitive (Ref 50, p 47). No compns of the above expls are given in Ref 50 

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A. F. Schlack, "Susceptibihty of Electric Primers and Electrostatic Discharges" ia Minutes of the 15th Explosives Safety Seminar, AD-775 580, NTIS, Spriugfield, Va., 1973. 

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. 

The mixtures were placed in transparent round latex flasks. Initiation was in the center. With their method, it was possible to record spherical detonation waves whose velocities were the same as when these mixtures were detonated in tubes. The waves usually originated very near the ignition source (electric spark or electric primer), but in some cases there was a brief predetonation period... 

Primers used in small arms and field artillery weapons were of the nonelectric type, but in stationary cannons, such as in coastal artillery or in Naval cannons, electric primers could be used... 

More extensive use of electric primers began in this century with the appearance of guns used in AC (aircraft), such as of cal 20mm. 

As firing by electric primers is much quicker than with mechanical primers (almost instan-... 

Electric Primer. This type is fired by the heat generated when an electric current passes thru a resistance wire or conductive primer mixture embedded in a primer compn. It was formerly used in harbor defense and railroad artillery ammunition (Ref 15, p 117), but is... 

Fig 53 COMPARISON OF ELECTRIC PRIMER WITH PERCUSSION PRIMER... 

Electric Primer MK34 Mod O is similar in construction to MK15 primer, except that it is designed for electrical initiation only and cannot be activated by percussion (Ref 52, p 2-129)... 

Similarly to electric primers, (described in Section 4, Part E), these electric detonators may be made to fire from suitable sources of electrical energy, such as generators, batteries or charged condensers they may thus be made to fire from an electric pulse supplied by energy stored within fuze firing circuit or by an electric pulse generated within the fuze system prior to or at impact... 

Accdg to definition given in Ref 23, p 3-22 (slightly reworded) It is an initiating explosive - train component fired by an electrical impulse supplied by the energy either stored within the fuze before release of the missile, or generated within the fuze system just prior to or at impact of the fuze. An electric primer serves to initiate the next component of the train which can be either a detonator or delay element... 

Electric primers possess many advantages over either the stab or oercussion primers, as can be seen from description given in Ref... 

Metals for components of electric primers are chosen to be compatible with the expls used. In primers using XC-9 compn or Pb styphnate, Cu is suitable (unless moisture is present), while in primers contg LA either A1 or stainless steel must be used to avoid formation of supersensitive " Cu azide... 

The spray metal" technique was invented in order to obtain good contact between extremely thin and short bridge wires and leads. Such bridges are used in newer type electric primers which are capable of being actuated by an extremely small energy input... 

Blasting machine) 335 (Cordeau Bickford) 336 (Primacord) 337-40 (Primers for propellent charges) 340-43 (Electric primers) 343 (Igniting primers) 343-65 (Fuzes, boosters and adapters)... 

For Combination (Percussion, Electric) Primer M75, the requirements of Spec MIL-P-46279 (Ord) (I960) include the following tests ... 

These drums were projected from a mortarlike, smooth-bore barrel, called the liven s Projector. It had an 8 bore and was 37.5 long. A propellant charge ignited by an electric primer was used to obtain a maximum range of 1450 yards... 

Cyclotol (50/50—RDX/TNT). Chauyaku Denki bakkan. Electric Primer... 

Dokasaku. Safety Fuse Powder Train Electric Primer. Denki bakkan... 

Primers, Military (US) (Table E9 on p E57 gives electrical characteristics and compos of explosive trains of Electric Primers XM85, 87, 88 and 89) Electric Squib, MK1, All-Purposes (Vol 5, p E59-L) Electro-Explosive Devices (Vol 5, pp E63 L to E64-L)l Electro-Explosive Devices, Pulse Firing (Vol 5, p E65) Electro-Explosive Device, Thin Film for (Vol 5, p E68-L)... 

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