US2194480A - Noncorrosive priming composition - Google Patents

Description

nonoonnosivs Y G CODSETION Charles H. Pritham, Upper Darby, and Ernest E. chel and Thomas Stevenson, Philadelphia,

No Drawing. Application March '7, 1938, Serial No. 1943M 6 Claims.

(Granted under the act of March 3, 1883, as

amendedApril 30, 1928; 370 0. G. 75'?) The invention described herein may be manufactured and used by or for the Government for governmental purpose without the payment to us of any royalty thereon.

This invention relates to a noncorrosive priming composition for small arms ammunition.

Although potassium chlorate compositions give excellent ballisti results, the corrosive residue left by this salt has been so objectionable that 10 nearly all manufacturers have attempted to develop suitable primer compositions without potassium chlorate. In order to obtain the required sensitiveness, however, it has been necessary to include an initiating compound with the usual fuels and oxidizers. Mercury fulminate was widely used at one time for this purpose, but the contamination of the cartridge brass with mercury made this compound objectionable when it was desired to reload the cartridge case. A number of substitutes for mercury fulminate were then proposed, such as lead styphnate, lead azide, diazodinitrophenol, andbther explosive compounds.

All noncorrosive priming compositions which have been proposed to date, however, have one common characteristic; namely, that they depend on a highly explosive chemical compound for their sensitiveness and igniting power. The storing and handling of such explosive compounds introduces a hazard into primer manufacture which was almost'nonexistent in the production of the old chlorate type primer. primer contains only insensitive ingredients that require no particular precautions in handling.

with these facts in mind, we have developed 85 a noncorrosive priming composition which, like the potassium chlorate primer, contains only fuels and oxidizers that are nonexplosive in themselves. The sensitiveness of this priming composition depends on the use of red phosphorous.

40 As a specific example, we have iound the following mixture suitable for small arms primers: I

This mixture may be blended and loaded into primer cups in the usual way. It has been found advantageous to use a small amount of glue or sum as a binder for the pellet.

The composition given above is merely one or The chlorate several noncorrosive priming mixtures which may be prepared with red phosphorous. Other oxidizers and fuels may be used, depending on the degree of sensitiveness desired. For example it may be prepared with other nitrates such as B strontium nitrate or basic lead nitrate,- In addition, peroxides of heavy metals may be used as oxidizing compounds.

Examples of other mixtures which are suitable for small arms primers are:

Per cent Red phosphorous 5 to 25 Zirconium metal 5 to'20 .Barium nitrate; 40 to Lead peroxide 10 to 25 15 Red phosphorous 5 to 25 Barium nitrate 40 to '10 Antimony sulfide '10 to 25 We are aware that red phosphorous compositions have been used for pyrotechnics, explosive or so-called spot light bullets, and for match heads. Red phosphorous compositions, however, have not heretofore been successfully used in 26 primers for small arms ammunition, and herein lies the novelty of this invention.

We claim:

1. A priming mixture consisting of red phosphorous 25% barium nitrate 58%, and antimony 80 sulfide 17%.

2. A priming mixture consisting of red phosphorous 5-25% barium nitrate 40-70%, and antimony sulflde'10-25%.

3. A primary mixture consisting of red phosphorous E's-25%, a nonexplosive and noncorrosive nitrateota metal 40-70%, and antimony sulfide 10-25%.

4. A priming mixture consisting of red phosphorous 525%, 9. nonexplosive and noncorrosive oxidizing agent 40-70%, and a nonexplosive and noncorrosive fuel 10-25%. 5

5. A priming mixture consisting of red phosphorous, barium nitrate, and antimony sulfide.

6. A primin: mixture consisting of red phosphorous, a nonexplosive and noncorroslve oxidizins aunt. and a nonexplosive and noncorrosive CHARLES H. rarrnm. manner a. RECHEL; THOMAS s'rnvnnson.