Primers, small arms

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)... 

Malfunctions of small arms ammo using the M34 primer have been related to inadequate control of pellet wt in the primer, with low pellet weight causing hangfires in the weapon. At the Army Mechanics and Materials Research Center (AMMRC), Watertown, Mass, NAA was investigated for 100% inspection of pellet wt in such primers (Refs 5 6)... 

Fig 4 is a sketch showing the components of typical primer caps for small arms cartridges,... 

AS of this writing, 100% inspection by NAA of small arms primers in an actual production loading plant has not been implemented, nor is it contemplated in the near future. Technical problems exist related to coupling the present state-of-the-art nuclear components with the high production rates for the primers, namely, tens of units per sec per automatic loading line. The high intensity of the neutron source and the complexity of the detection system required detracts from the utility of the method in a plant environment where simplicity and safety of operation are of paramount importance. Nevertheless, the technical feasibility of the method has been demonstrated by the AMMRC study and future developments in nuclear activation hardware may ultimately make this non-destructive inspection for production primers more viable... 

The same investigator (Ref 3) proposed the following primer mixts for small arms ammo ... 

Popping" A term used to designate the heat treatment of empty or Fired small arms ammo cartridge cases prior to shipping them as scrap. This treatment is necessary to insure that no unfired primers remain among the cartridges... 

Since the quantity of small arms ammo manufd and expended is extremely high, greater emphasis has been placed on an explanation of the primers used in these rounds. However, this in no way is intended to diminish the importance of additional types of percussion primers which find wide use in artillery ammo (Table 3)... 

E.R. Rechel, Small Arms Primers , Frank-fordArs Rept No 10 (1932) 3) C.W, Church-... 

T.Q. Ciccone, Summary Compilation of History and Technical Information of Small Arms and Cannon Primers , Battelle Columbus Laboratories Task Order No 75-265 (1977)... 

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... 

Primers used in small arms and field artillery weapons were of the nonelectric type, but in stationary cannons, such as in coastal artillery or in Naval cannons, electric primers could be used... 

Simple Primers consist of a housing (brass or copper cup) contg a primary mixture and parts, such as an anvil, or electrical bridge. They are used for igniting small arms proplnts by flash. For their description and cutaway views see next item (b)... 

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... 

Percussion primers used in current center-fire cartridges (See Ref 44, p C74-L) in US and NATO small arms are shown on Fig 31 is taken from TM 9-1305-200(1961), p 25 (Ref 42). Each of these primers consists of a small brass or gilding metal cup that contains a primer compn pellet. Present compns are mostly noncorrosive type, such as consist ing of LSt-LA. The older types contained usually MF, KCIOj Sb2Sj, with or w/o ground glass and a binder. A paper disk (foil), which serves... 

A small-arms primer will not initiate, by itself, an expl chge (Ref 42, p 24)... 

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... 

Hayes (1938), 572-78 (Propellent primers-percussion, friction, electric, combination and igniting) 578 (Fuze primers) 579-97 (Projectile fuzes) 624-25 (Historical on primers in military rifles) 658-60 (Small arms primers) 660 (Berdan primer)... 

High-explosive train) 181-84 (Small arms primers) 235-39 (Fuzes for hand grenades) 241-50 (Firing devices for antipersonnel mines and booby traps) 257 (Fuze for rifle grenade) 259-60 (Fuze for 2.36-inch rocket) 263-67 (Fuze for antitank mine) ... 

Stettbacher(1952), 124-33 (Explosivos de iniciacion) 134-39 (Cebos o capsulas detonadores - Blasting caps) 137 (Esto-pinas - Primers used in small arms cartridges) 137-38 (Mechas - Fuses) 164-66 (Sabotage devices includes 3 refs)... 

Primer compn for small arms ammo Tri-nitroresorcinol 15, Pb thiocyanate 20, K chlorate 50 Pb styphnate 15%) Ibid, USP 1416122(1922) (Similar to above but Di-plumbic di-trinitroresorcinol is used instead of Trinitroresorcinol) Ibid, USP 1416123 (1922) (Similar to above except that MF is used in lieu of Pb nitroresorcinol compds)... 

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... 

Grade 1 — For use in the manuf of MF (Mercuric Fulminate), Smokeless Propellant (where a denaturant is not required), small arms primers, and optical elements... 

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