Bomb Primer-Detonators

A bomb primer-detonator is an interchangeable unit (composed of a primer delay element and a detonator) which is designed to provide delay in the action of older models of tail fuzes. Primer-detonators of various time delays are available, with the exact delay time of each painted on the detonator head (Ref 51 a,... 

Method No 203. Primer Mix, New No 4 has been used principally in rifle grenade fuzes and bomb primer detonators. US Military Spec MIL-P-2499 (1950) requirements Moisture, max 0.30% and Composition MF 35, Sb sulfide 30 and K chlorate 35%... 

GP bomb Ml 17. The end of the fuze body which enters the adapter is threaded internally to receive primer-detonator Ml4. 

Its dimensions, weight, primer, detonator, and booster are identical with those of M130A1 fuze. The fuze is provided with an antidisturbance device which is very sensitive and, when the fuze is fully armjed, the bomb is very dangerous to handle and no attempt should be made to disarm it. 

Inert fuzes are provided for training ground crews in assembling handling of bombs, and also for classroom instruction of ordnance personnel. These fuzes are standard items, except that explosive components (primers, detonators, delay relay elements and boosters) are removed (Ref 51a, p 4-107)... 

Under this title are included bomb adapter-booster, auxiliary boosters, primer-detonator, delay elements, bursters and igniters... 

Trench mortars, historical) 276 (Ignition cartridge and fuze for 3-inch trench mortar ammo) 279 283 (Ignition cartridges for 81-mm trench mortar) 291-318 (Trench mortar fuzes) 319-23 (Artillery fuzes-his-torical, classification and forces available to cause artillery fuzes to function) 326-28 (Percussion primers American M36 and Berdan M37 for 2 0-mm shells) 328, 337, 340-42, 356-57, 369-76, 383-99, 435-44, 455-56, 462, 469-71, 484, 497-502, 525 532-33 (Fuzes for various caliber artillery ammo) 331-35, 364-66, 403-07, 510, 528 541-45 (Primers, percussion for various caliber artillery ammo) 557-62, 580-91 606 (Bomb fuzes) 579-80 (Primer-detonators for bombs) 623-32 (Depth bomb fuzes) 643-52 (Fuzes for fragmentation bombs) 668-71 (Chemical bomb fuzes) ... 

All bombs, except the very largest, are packed in wooden boxes or crates. The fin assemblies for the larger bombs are also crated when packed separately from the bombs. Some bombs are packed with fuzes inserted but with primer-detonators removed. However, rhe fuzes are usually removed and packed in sealed moisture-proof containers. In the latter case the fuze wells in the bombs must be closed with plugs. Some fuzes are packed in the same containers with the bombs, others separately. Bombs and components are stored as shipped. Complete rounds should not be assembled in advance of requirements and assembled rounds should be carried with sealing wires and safety in place at all times until installation in the plane. The arming wire should remain in place until the bomb is released, or until the safety pins and sealing wire are replaced and secured... 

III) Detonation or Explosion., It can be conducted either by initiating the expls contained in ammo, or by the force of detonation of other expl material s placed in contact with the item. Ammo items which can be destroyed by these methods include artillery shells, aerial bombs, mortar shells, shrapnel shells, photoflash bombs, antitank mines, rockets, grenades (hand and rifle), loaded metal components (such as fuzes, primers, detonators, boosters bursters) and pyrotechnic... 

Method Attached the primer cord to the first bomb s detonator. Theory was that when the detonator exploded it would set off the primer cord as well. This primer cord would set off the second bomb simultaneously. 

The items used for military purposes include those used for small arms ammunition, artillery ammunition, rocket ammunition, aircraft bombs, land sea mines, grenades, demolition devices and pyrotechnic devices. As some items (such as detonators, primers, etc) can be used in several kinds of ammunition our write-up might contain some repetitions... 

If the fuze has been set for "delay action" (usually 0.1 sec), the detonator is aligned with the delay expl components. Impact fires the delay primer. The flash from the primer sets off the BkPdr delay element which burns thru and sets off, respectively, the relay, the detonator, the booster lead-in, the booster and the main charge of the bomb. More detailed description of the AN-M103A1 fuze, especially of its arming mechanism is given in Ref 51a, pp 4-1 to 4-6... 

Before release. Before the fuzed bomb is released, the arming wire prevents the arming vane from turning. The end of the firing pin in the hole in the rotor holds the rotor in the unarmed position with the primer out of alignment with the arming pin and detonator... 

If the bomb strikes with the vane end toward the target, inertia causes the primer holder (11) to move toward the striker (12) compressing its spring (6) and forcing the primer (7) to hit the firing pin (5). Flame from the primer initiates the detonator (8) which causes detonation of Tetryl booster (10) and bomb filler... 

When the primer is struck by the firing pin, it flashes and sets off the delay element. After burning thru, the delay element sets off the relay which fires the detonator and the bomb (Ref 51a, pp 4-36 to 4-38)... 

The firing pins cause the primers to ignite and the resulting flash sets off the delay elements, which are followed by relay elements, detonators, auxiliary booster lead-ins, booster leads, booster and main charge of the bomb (Ref 51a, pp 4-44 to 4-47)... 

Bomb Nose M.T Fuze M129 (Fig 4-24), designed for aerial burst or impact, is used only with the fragmentation (butterfly) bombs assembled in clusters. Its body diam is 1.75-in, overall length 3.0-in, and wt 0.4-lb. It is equipped with primer M41A1, detonator M31, and booster contg Tetryl pellet in a metal cup... 

Detonation. The firing pin sets off the primer which relays the explosion to the detonator. The detonator explodes the booster which, in turn fires the bomb... 

Bomb Nose Fuze, M111A2 is similar in appearance (but shorter in length) and operation to the fuzes AN-Ml46-series (shown here in Figs 4-27 4-28), except for the absence of the detonator slider and its cover plate and lock pin assembly. Its percussion primer is always in line with the firing pin. 

Incendiary bomb fuzes) 720-21 (Flare fuze) 723, Fig 282 (Primer for airport flare) 725, Fig 283 (Built-in fuze for photoflash bomb) 12a) K.S. Warren, "Compilation of Data on the Composition of Foreign Primers and Detonators", PATR 1450(1944)... 

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