Initiation by projectile impact

Initiation by Bullet Impact is a special case of Initiation by Projectile Impact. See Bullet Tests in Vol 2, pp B332-340 and Vol 4, p D153 also under Projectile Impact below... 

Initiation by Projectile Impact is a complicated process which depends on a combination of shock initiation, impact initiation and hot fragment initiation effects. For fast projectile impact, shock initiation effects are predominant. With slow projectiles the initiation resembles Impact Initiation. Further complications are introduced if the impacting projectiles are hot a special case where the explosive is part of the projectile is the so-called Susan Test—see Barrier Tests Their Comparison with Shooting Tests in Vo 4, pp D145-147 and Detonation (and Explosion) Experimental Procedures in Vol 4, pp 333-335... 

Grosse et al, JACS 79, 6341-42(1957) (Initiation to deton of liquid oxygen-liquid methane solns) 21) K.E. Spells D.W. Woodhead, Nature 179, 251-52 (1957) (Initiation of deton by projectile impact)... 

James, H.R. Critical energy criterion for the shock initiation of explosives by projectile impact. Propellants, Explosives, Pyrotechnics 13, 35-41 (1988). 

The work reported here indicates that a critical energy criterion as postulated by Walker and Wasley and modified by James can provide a useful model of prompt shock initiation in projectile impact experiments. However, it is important that the shocked volume is accurately estimated. It is at least likely that it is the failure to take into account rarefactions in the barrier material which account for the different critical energy values required to give the best fits to our data with metal and PMMA barriers. Figs 6-8. 

Metallic K. in admixtures with Ag or Hg oxides or chlorides, or in contact with chlf or carbon tetrachloride, can be expld by strong impact (Ref 3). Such mixts were proposed by Staudinger (Ref 1) for use as initiating expls for blasting or in bursting projectiles... 

Its detonation is transmitted thru booster lead to booster and then to the main chge of projectile. Detonation may also be caused by graze impact. In this case, an inertia-operated firing pin overcomes a creep spring and initiates the stab primer M97, which, in turn, shock initiates the electric detonator M69 (Ref 52, PP 5-55 5-56 Fig 5-38 on p 5-56)... 

An experimental study of the projectile impact initiation of detonation in cased explosives has revealed both shock and non-shock regimes. The shock regime can be described by an empirical critical energy criterion for detonation. However, a full description of the processes leading to detonation or to violent reaction cannot be based on such a criterion and requires a full description of hot spot formation and growth mechanisms. 

Fuze, Point Initiating Base Detonating (PIBDF). A fuze with initiating components located in the forward end of projectile, while detonating components are located in the base of projectile. It is designed to be Activated by impact... 

It is a single-action, SQ type designed for use with 57-mm HEAT projectiles. The fuze differs from PD fuze s in that initiation is by impact of the fuze primer directly against the target. The fuze is characterized by internal threads for engagement of the projectile and by shaped auxiliary detonating charge (H). 

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