Primer charge

Pour a small quantity of flash-powder into the bore to cover the glow plug. Tap the barrel lightly to make sure that the powder flows into contact with the filament. This is the primer charge. Pour about one grain of pistol powder to cover the primer charge. Tamp in place with a small wad of cotton. 

Air Gap Sensitiveness to Detonation (and Explosion). It is a term which has been applied to the maximum distance of the consistent propagation of detonation by influence from a primer charge across an air gap to a receptor charge. The air-gap test for sensitiveness has been used for many years as a control test for dynamites and other commercial expls. 

Initiation by Primers (and Boosters) is the standard method of initiating secondary explosives. Thus hot wires (or other means) are used to initiate the primer charge (Lead Azide, Mercuric Fulminate etc) explosive whose detonation then initiates the main charge of PETN,... 

RDX etc. For insensitive explosives such as TNT, ANFO etc an intermediate booster charge (PETN, RDX, Tetryl, NG Dynamites etc) may be necessary between the primer charge and the main charge. For details, see Minimum Priming Charges in Vol 8 Booster in Vol 2, pp 243-246 Contact Detonation Sensitivity Test in Vol 4, pp D186-190 and the added reference of C. H. Johansson T. Sjolin, ONR SympDet (1965) p 435... 

Base charge. A standard blasting cap shell may be charged with. 16g of nitroinulin (13.75%N) pressed under 7840 psi, and provided with a primer charge of 0.3g of 80/20 fulminate-K chlorate mixt. Such a cap was found to be satisfactory for the detonation of explosives Ref 1) W. deC. Crater, USP 1992123 (1933)... 

Kibakuzai. Primer Charge. See Chikkaen (Army) or Chikka namari (Navy), meaning LA (Lead Azide) and also Raiko (Army) and Raisan suigin (Navy) for MF (Mercuric Fulminate)... 

The results on the irradiated M26 primers and M19A2 detonators are shown in Fig 11. The primer charge contained only 5% Pb azide while the detonator contained the same primary charge plus 250mg Pb azide and 142mg Tetryl. it was determined that with a total gamma dose of 9.7 x 107 R (90 day exposure), 92% failures were obtained in the stab tests on a sample of 100. The failures were attributed to the deterioration of the Pb azide (the Pb azide did initiate but failed to initiate the Tetryl charge)... 

Primadet = mild detonating fuse (USA) 218 primary blast 267 primary explosives 191 267 primer 94 267 primer charge 267 produits de detonation = fumes 145 progressive burnig 158 267 projectile forming (shaped) charge 283... 

Trade name for primer charges with special delay inserts consisting of a sensor on one end and an aluminum shell delay cap on the other. Delay times 0-500 milliseconds in 25 ms intervals. The Deckmaster-unit has to be connected with detonating cord with no more than 30 grains per ft (-< Miniaturized Detonating Cord). For varied delay steps in the hole, only one downline detonating cord is needed. 

Minimum current that must be applied to an igniter circuit for reliable ignition of the primer-charge without regard to time of operation. 

Its compn by wt is Thermite 68.7, Ba nitrate 29.0, S 2.0 and oil (binder) 0.3%. In the bomb, a TH3 core is ignited by a primer charge, the burning core then melts and ignites the Mg alloy body of the bomb. The incendiary action on the target is localized since there is little scattering of the incendiary material... 

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