Lead azide minimum initiating charge

Fig. 58. Minimum initiating charge of lead azide, lead styphnate and their mixtures for 1.25 g of tetryl, according to Grant and Tiffany [40].

Impact tests indicate composition C4 is less sensitive than composition C3. The rifle bullet test results, with only 20 percent of the vials burning, also indicate less sensitivity. Composition C4 is unaffected in the pendulum friction test and has a five second explosion temperature of 263°C to 290°C. The minimum initiating charge required is 0.20 grams of lead azide or 0.10 grams of tetryl. 

Table Vll shows how the process used to manufacture lead azide, or the consequent product, significantly affects the quantity required to initiate a standard secondary explosive, RDX, in the stab-sensitive detonator (Figure la). Dextrinated lead azide has a lower output because it is less compressible and has more diluent namely, 8.5% dextrin compared to the 3.5% carboxymethyl cellulose (CMC) [34] in RD 1333, 2% polyvinyl alcohol in PVA lead azide, and no binder in Service lead azide (see Chapters 1 and 2). This situation is shown quantitatively in Table VII, which shows the minimum charge weights of each...

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