Premature explns

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... 

When an identical round was placed in the barrel after 125-round burst, premature expln of the bullet occurred with bulging of the barrel... 

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... 

V. Galvanic Action Electric Currents are those caused when dissimilar metals contact each other directly or thru a conductive medium. For example, when in seismic shooting an aluminum loading pole replaced the heavier wooden pole, two premature explns took place. This happened because the combination of aluminum and its steel casing in the alkaline drilling mud formed a sort of battery... 

As NG is very dangerous to handle, many premature explns took place in the past, causing the loss of life and property. Because of these facts, the DuPont Co has worked for years towards the complete elimination of liq NG in its well shooting activities. This goal was finally achieved beginning in 1951 and NG has now been replaced by a series of better and safer expls, such as "DuPont SNG (solid... 

The formation of one or more cavities(air spaces or voids) in cast-loaded solid, expl or proplnt c hges is called cavitation (See under Loading of Ammunition). A cavity in a HE chge of a shell may cause premature expln in the gun because of collapse of the chge under the force of acceleration. A cavity in a propint chge may affect its ballistic characteristics(Ref 1). Cavities in loaded ammo may be discovered by x-ray devices such as Betatron(qv)... 

Cracks or voids in the expl fill of an artillery shell are hazardous because they have the potential of causing a premature expln before the shell leaves the gun barrel. Shells are therefore in-... 

The strength of these two expls was about equal to that of 70% Dynamite, but they were much more sensitive to impact. They could be initiated with a fulminate blasting cap, but if the cap material was Cu, it could be eaten thru by the nitric acid, thus causing premature expln of the fulminate... 

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