Small arms ammunition primers

Useful for pyrotechnical fire transfer are the A/39 (Army) mixture, Formula 7 mixture PA-lOl, Formula 8, said to be particularly well-suited for the ignition of delay compositions FA-70, Formula 9, used in numerous pyro primers such as the M19 and in commercial small arms ammunition primers, e.g. Winchester 8-1/2 NOL-60, Formula 10 and FA-959, Formula M. Red phosphorus in combination with barium nitrate and other materials has been used in several formulas in percussion primer mixtures and is also the subject of a patent. ... 

Primer A term for the device used to ignite smokeless powder in small arms ammunition. An impact-sensitive composition is used. When struck by a metal firing pin, a primer emits a burst of flame capable of igniting the propellant charge. Several typical primer mixtures are given in Table 6.2. 

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... 

The complete round (cartridge) of small arms ammunition (except for the shotgun), employing one of the center-fire obturated type primers is represented in Fig 32... 

Hangfire Primers. A hangfire in small arms ammunition (initiated by a blow from a firing pin) can be defined as that condition which exists when initiation of the usual chain of events following the release of the trigger in a loaded weapon, occurs at a rate slower than normal the definition of hangfire for electrically initiated ammo is similar... 

Army Factory Capua (Pirotecnico Eser-cito) (Caps, Primers, Small Arms Ammunition) 11) Nobel SGEM Factory in Taino, near Varese (Detonators, Blasting Caps, Primers, Fuses, Primary Explosives (now closed)... 

Under high pressure powdered PETN agglomerates to a mass which has the appearance of porcelain, but which, when broken up into grains, is a very powerful smokeless powder functioning satisfactorily with the primers which are commonly used in small arms ammunition. The powder is hot and unduly erosive, but cooler powders have been prepared by incorporating and compressing PETN in binary or in ternary mixtures with TNT,... 

NCNM primer mixtures, it was not until the early 1950s that U.S. military ammunition became noncorrosive. This was because early NCNM commercial priming mixtures suffered erratic ignition and unsatisfactory storage stability, and as large quantities of small arms ammunition are stored as a war reserve, military ammunition must have unquestioned reliability and storage stability. 

These primers can be used not only in small arms but also in some pyrotechnic devices and fuzes. All simple primers are small in size, 0.21 to 0.31 inch in diam and 0.12 to 0.23 inches long for rifle ammunition and slightly Smaller for carbines. They contain only one small charge of primary expl or a mixture which must have sufficient sensitivity to be initiated either by the crushing or stab action of a firing pin... 

Blowback An escape of gas under press to the rear, on firing small-arms or fixed or semi-fixed artillery ammunition, is called a blowback. This may be caused by ruptured cartridge, pierced primer, primer leak, blown primer or primer set -back. The term also applies to the recoil of an unlocked bolt in a firearm Refs 1)TM 9-1910( 1955),p 231 2)Glossary of Ord(1959),39... 

Uses In priming compositions for igniting charges of smokeless powder (small arms) for igniting the black powder in primers of artillery ammunition, and for igniting the black-powder igniters in separate-loading ammunition. 

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