US2035471A - Propellent powder - Google Patents

Description

Patented Mar. 33, 1%36 George C. liliaie and Donald R. Cameron, Dover, N. ii.

No Drawing.

QFFEQ Original application March 2%,

1934, Serial No. 716,512. Divided and this appiication September 118, 1935, Serial No. 41,110

2 Claims.

(Granted under the act of March 3, 1883, as amended April 30, 31928; 370 Q. G. 757) and at the same time yields only a-thin, fugitive smoke which is decidedly less visible than that The invention described herein may be manuiactured and used by or for the Government for governmental purposes, without thepayment to us of any royalty thereon.

5 This invention relates to a propellent powder, and is a division of copending application, Serial No. 716,512 filed March 20, 1934.

' The requirements of a propellent powder for military weapons are low volatility, resistance to smokelessness, and fiashlessness.

It is recognized by those experienced in the preparation of propellent powders that no powder has been produced to date which fulfills all the requirements above cited to the desired degree under all circumstances. Thus. a particular powder may be acceptable for use because it offers advantages in fulfilling one or more of the requirements above mentioned even though it does not offer any particular advantage with respect to other of the requirements, but although acceptable, such a powder is obviously not all that is to be desired.

One of the principal difliculties in preparing guns resides in the fact that the common methods of eliminating flash involve the addition to the powder composition of ingredients which have the objectionable tendency of producing smoke when the powder is fired. The user is, therefore,

confronted with the problem of choosing between a' powder which flashes but produces a minimlun of smoke and a powder which is flashless but produces more smoke than is really desired- The purpose of this invention is to provide a non-hygroscopic, non-volatile and stable nitrocellulose propellent powder which is absolutely flashless and produces less smoke than powders heretofore in use. This purpose is accomplished by incorporating in the powder composition a relatively small amount of triacetin. The triacetin is the pure product or mixtures of it with small amounts of diacetin and monacetin such as are obtainable commercially under the name triacetin.

It has been found by firing powders made from compositions containing nitrocellulose and triacetln that the triacetin is very eflicient in reducing the flash from the nitrocellulose powders moisture absorption and chemical decomposition,

powders which yield no flash at the muzzle of produced by any other flashless powders.

example of a composition is given which has been thoroughly tested in 37 m/m and 75 m/m 5 military weapons and found to be not merely satisfactory but distinctly superior to other fiashless powders from the standpoint of the amount of smoke produced when fiashlessness is consistently obtained.

Nitrocellulose Triacetin Per cent others.

The length of the tube or barrel of the gun is one factor since along tube permits greater radiation of heat from the gases before they issue from the muzzle and it is therefore easier to reduce the temperature of the gases below 30 their inflammation temperature by the flash reducing agent employed in the powder. Thus with I some weapons which have along tube and require relatively small amount of propellent powder to meet ballistic requirements, the addition of 2% triacetin may be suflicient to eliminate flash while with a gun or howitzer which has a short tube and requires a much larger amount of propellent charge, 5% or even 10% of the triacetin may be needed. If the percent of this constituent is varied 40 the percentage of the nitrocellulose must of course be changed accordingly.

We claim.

1. A propellent powder consisting of nitrocellulose and triacetin.

GEORGE C- HALE. DONALD R. CAMERON.