US1779821A - Priming composition - Google Patents

Description

Patented Oct. 28, 1930 UNITED STATES PATENT OFFICE f J'OSEPH D. MCNUTT, OF NEW HAVEN, CONNECTICUT, ASSIGNOR, BY MESNE ASSIGN- HENTS, TO WINCHESTER BEPEATING ARMS COMPANY, OF NEW HAVEN, CONNECT- ICUT, A CORPORATION OF DELAWARE PBIM'ING COMPOSITION Ho Drawing. Application filed June 21,

This invention relates to improvements in priming mixtures and more particularly to a non-corrosive priming mixture for center fire cartridges.

6 r In producing the priming mixture forming the subject matter of this invention, I employ as the chief oxygen supplying element, a metallic nitrate, as the fuel element, a metallic sulphocyanate and as the detonating element,

10 a metallic fulminate- To these ingredients I add a small percentage of charcoal and a small percentage of barium carbonate. I am aware of the use of a metal nitrate, a metal sulphocyanate and a metal fulminate together with ground glass or other suitable abrasive as a non-corrosive rim fire priming mixture, but prior to my invention I am unaware of any prior center fire non-corrosivepriming mixtures containing these substances, alone or in combination with other substances.

The use of charcoal softens the mixture and apparently makes it more readily ignitable thereby permitting the use of a non-corrosive mixture of this type in center fire cartridges.

While the quantity of charcoal used is small,

its presence is apparently important and is practically essential to the ultimate success of the mixture.

A suitable priming mixture for center fire use may be formed by mixing the ingredlents in the following proportions:

Per cent Barium nitrate 45 Lead sulphocyanate 16 Charcoal 2 Barium carbonate 2 Mercury fulminate The proportions of these ingredients may, of course, be varied, depending upon the commercial strength of the ingredients and to meet the requirements of various uses of the mixture.

In mixing the ingredients I depart from the usual practice and place the mercury fulminate in the mixing machine first. The usual gum solution is then added and the mixing machines started. The dry ingredients are first screened, then placed in the mixeo ing machine containmg the mercury fulmi- 1928. Serial No. 287,354.

nate and gum solution and the whole mixed for about five minutes. After the mixture is removed from the machine, it is kneaded by hand for about ten minutes.

The mixture is then formed into individual pellets of the proper size for the individual charges in the usual manner on a charge plate containing perforations of the proper size to receivefthe charges. These pellets are then transferred to primer cups arranged in perforations in a second plate by bringing the perforations in the two plates into alignment with each other and pushing the pellets into the cups. A charge of .6.65 grains is used for a cartridge of the size of the .30 Governture has been charged into the cups, the charged cups are submitted to pressure by means of the usual apparatus and the primers then inserted in the shells. The shells may be loaded with powder and bullets in the usual manner.

I claim:

1. A priming mixture consisting essentially of more than 40% of barium nitrate, substantially 35% of mercury fulminate, substantially 16% of a lead sulphocyanate, substantially 2% of barium carbonate and substantially 2% of charcoal.

2. A priming mixture consisting essentially of substantially barium nitrate, substantially 35% mercury fulminate, substantially 16% of lead sulphocyanate, substantially 2% barium carbonate and substantially 2% of charcoal.

3. A. non-corrosive priming mixture con slsting essentially of barium nitrate, lead sulphocyanate, mercury fulminate and charcoa JOSEPH D. McNUTT.

.ment 06 cartridges. After the priming mix-