primer

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primer

explosives

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July 13, 2026

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A primer is a small amount of easily detonated explosive used to ignite a larger explosive charge, known as the main charge. In blasting caps, a primer composition produces a burst of flame to ignite a detonator, which then initiates the main explosive charge. Primers can be set off by heat, friction, or mechanical shock.12

Some explosives, like Nitramon, are insensitive to common initiation methods and require a large, specialized primer, such as the Nitramon primer, for detonation. Ammonium picrate, used in armor-piercing projectiles, also requires a suitably insensitive primer to detonate effectively after penetrating armor.34

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fuse
It is distinct from the primer or firing pin that initiates the launching of a rocket or artillery shell. Impact fuzes function as they hit the target. Time fuzes delay the functioning for a certain period from the starting time. Command fuzes function on signal from a remote-control point. Proximity…
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It is distinct from the primer or firing pin that initiates the launching of a rocket or artillery shell. Impact fuzes function as they hit the target. Time fuzes delay the functioning for a certain period from the starting time. Command fuzes function on signal from a remote-control point. Proximity…
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blasting cap
…shock wave, and the term primer, or priming composition, denotes a substance that produces a sudden burst of flame to ignite the detonator. The primer may be set off by the brief application of heat (from a burning fuse or an electrically heated wire), by friction, or by mechanical shock…
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…shock wave, and the term primer, or priming composition, denotes a substance that produces a sudden burst of flame to ignite the detonator. The primer may be set off by the brief application of heat (from a burning fuse or an electrically heated wire), by friction, or by mechanical shock…
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ammunition
…projectile, the propellant, and a primer that ignites the propellant. Other components such as cartridge case, fuze, and bursting charge are frequently included.
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…projectile, the propellant, and a primer that ignites the propellant. Other components such as cartridge case, fuze, and bursting charge are frequently included.
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mining
Horizontal openings: drifts
…of the delay is the primer, an explosive (generally lead azide, mercury fulminate, or pentaerythritol tetranitrate [PETN]) that, upon detonation, releases a great deal of energy in a very short time. This is sufficient to ignite the larger amount of ANFO explosive packed into the hole. The most common time…
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…of the delay is the primer, an explosive (generally lead azide, mercury fulminate, or pentaerythritol tetranitrate [PETN]) that, upon detonation, releases a great deal of energy in a very short time. This is sufficient to ignite the larger amount of ANFO explosive packed into the hole. The most common time…
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