Detonation premature

Cilatvor or Silatvor. From the Russian word clla (sila), which means force , and tv or it, which means to create . Accdg to J. Daniel, Dic-tionnaire des Matieres Explosives , Dunod, Paris, p 716, Silatvor was an expl mixt based on nitrated non-resinous sawdust. It resembled Schultze s Pulver (qv) and was tried in 1886— 1887 as a bursting charge in shells and torpedoes to replace BlkPdr. It proved not to be safe to use as a bursting charge because it detonated prematurely. It could not be used as a proplnt... 

On a hydro-electric scheme that I worked on in Malaysia there was a rather distressing accident when the face which had been charged up detonated prematurely. There were several injuries. The only explanation which could be offered was that lightning had travelled up the rails from the portal to the face. (The portal was high up on an exposed hillside and there was a thunderstorm at the time.) This was never really proved, but nobody could suggest any other explanation. Have the Authors come across anything like this ... 

In addition, H2 is extremely sensitive to spark initiation, and can cause premature detons when ammo is being handled, is in-tube during launch, or is being steam-cleaned for reloading, purposes. A parallel reaction involves the release of NH3, which can combine with metals such as Cu in the presence of nitrates to form such extremely shock sensitive compds as tetramino cupric nitrate (Ref 17). To obviate these effects, desiccants such as silica gel may be added to the extent of 0.5% (Ref 12)... 

Although RDX and HMX are adequate for military applications, they are by no means perfect. The risk of premature detonation increases when such explosives are used in shells for high calibre guns due to the higher set-back force. Also of concern is the risk of catastrophic... 

Fuzes contain safety devices that tend to prevent functioning until after the fuze has been subjected to centrifugal and setback forces, after the round is fired. In the so-called bore-safe fuzes, the path of the explosive train is interrupted so that, while the projectile is still in the bore of the weapon, premature expln is prevented should any of the more sensitive fuze elements (such as primer and/or detonator) start to function. Interruption is usually achieved by inserting out-of-line components or interrupter blocks or slides. Although this leaves the fuze in an unarmed position, it would not be considered safe in handling or shipping, unless the fuze was not provided with safety devices such as safety wires or cotter pins. These outside devices must be removed prior to inserting the fuzed round of ammunition into gun barrel, but the fuze will still be unarmed because some of its inside parts are not free to move to their proper positions so that the fuze may operate in its intended manner... 

Fig l-99a given here represents cutaway and rear views of fuze, while Fig l-99b shows its attachment to the demolition charge M3A1. The shield shown on Fig 1-100 serves as a bracket for mounting the fuze and protects it from premature detonation Fuze M1A1 can also be used with "bangalore torpedos" which are described in vol 2 of Encycl, p B16-R (Ref 44)... 

Some-defect in construction of the fuze or of the booster might cause a premature but such cases are comparatively rare. If the fuze or booster detonates it causes complete detonation of the bursting charge... 

Similar unsatisfactory cook-off prematures were obtd with Caliber. 50 Explosive Bullet developed by die Hunter Manufacturing Co and submitted in 1943 to tests at Aberdeen Proving Ground. The bullet had a firing pin, a LA detonator, an arming wire in the nose, and an expl chge of 15 grains of Tetryl... 

The idea of separating, by a metallic sheath, die bursting charge of a projectile from the booster belongs to Sir R. Robertson and dates to die time of WW1. It was done in order to eliminate the possibility of premature explns caused by set-back. In its original form, the device was intended to detonate an insensitive expl such as Amatol. It consisted of a strong steel tube, 3 inches long and J4 inch (hick, screwed into the... 

Later they proved to be very effective for underwater explns. Two Penthrinits, 1 2 of Table 17 were, accdg to Stettbacher (Ref 6), loaded in 1929—1930 in 2cm shells and tested at Oerlikon Fabrik at muzzle velocity (vQ) 840m/sec. No prematures occurred. The addition of about 15% A1 powder increases the efficiencies of Penthrinits, while high amounts seem to decrease it. For example, addition of 30% A1 to formulation 1 of Gelatine Penthrinits decreased detonation velocity from 8000m/sec to 7200... 

One problem with the whistle mixes investigated by Maxwell is their sensitivity to accidental or premature detonation. EUem (Ref 2) gives the formula (No 160 of Table 1) for the reputedly... 

Bore Safe Fuze. Certain fuzes are considered to be boresafe(detonator safe) if the expl train is interrupted so that, while the projectile is still in the bore of the weapon, premature action of the bursting chge is prevented should any one of the more sensitive elements (primer or detonator) accidently function(Refs 1,2, 3). 

Cook-off. The premature deflagration or detonation of ammunition caused by the absorption of heat from its environment. Usually it consists of the accidental and spontaneous discharge of, or expin in, a weapon, caused by an overheated chamber or barrel igniting a fuze, proplnt charge or bursting charge Ref OrdTechTerm (1962), 84... 

The high explosive in the shell must be so insensitive that it will tolerate the shock of setback without exploding. Trinitrotoluene (TNT) is generally considered to be satisfactory for all military purposes, except for armor-piercing shells. The explosive must be tightly packed within the shell. There must be no cavities, lest the setback cause the explosive to move violently across the gap and to explode prematurely while the shell is still within the barrel of the gun, or as is more likely, to pull away from the detonator and fail to be exploded by it. 

Remove the positive safety. If it will not come out easily, this means that the striker is probably pressed against it. Do not force it out. This may cause premature detonation. Replace the fuze. 

Keep all leg wires neatly rolled up and tied together as a deterrent against errant radio transmissions that could cause premature detonation. 

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