Smokeless Powder - Propellent Improvements

Propellent Improvements

In 1863 Prussian artillery captain Johann F. E. Schultze patented a small arms propellent of nitrated hardwood impregnated with saltpetre or barium nitrate. Prentice received an 1866 patent for a sporting powder of nitrated paper manufactured at Stowmarket, but ballistic uniformity suffered as the paper absorbed atmospheric moisture. In 1871 Frederick Volkmann received an Austrian patent for a colloided version of Schultze powder called Collodin which he manufactured near Vienna for use in sporting firearms. Austrian patents were not published at the time, and the Austrian Empire considered the operation a violation of the government monopoly on explosives manufacture and closed the Volkmann factory in 1875. In 1882 the Explosives Company at Stowmarket patented an improved formulation of nitrated cotton gelatinised by ether-alcohol with nitrates of potassium and barium. These propellants were suitable for shotguns but not rifles.

In 1884, Paul Vieille invented a smokeless powder called Poudre B (short for poudre blanche -- white powder, as distinguished from black powder) made from 68.2% insoluble nitrocellulose, 29.8% soluble nitrocellusose gelatinized with ether and 2% paraffin. This was adopted for the Lebel rifle. It was passed through rollers to form paper thin sheets, which were cut into flakes of the desired size. The resulting propellant, today known as pyrocellulose, contains somewhat less nitrogen than guncotton and is less volatile. A particularly good feature of the propellant is that it will not detonate unless it is compressed, making it very safe to handle under normal conditions.

Vieille's powder revolutionized the effectiveness of small guns, because it gave off almost no smoke and was three times more powerful than black powder. Higher muzzle velocity meant a flatter trajectory and less wind drift and bullet drop, making 1000 meter shots practicable. Since less powder was needed to propel a bullet, the cartridge could be made smaller and lighter. This allowed troops to carry more ammunition for the same weight. Also, it would burn even when wet. Black powder ammunition had to be kept dry and was almost always stored and transported in watertight cartridges.

Other European countries swiftly followed and started using their own versions of Poudre B, the first being Germany and Austria which introduced new weapons in 1888. Subsequently Poudre B was modified several times with various compounds being added and removed. Krupp began adding diphenylamine as a stabilizer in 1888.

Meanwhile, in 1887, Alfred Nobel obtained an English patent for a smokeless gunpowder he called Ballistite. In this propellant the fibrous structure of cotton (nitro-cellulose) was destroyed by a nitro-glycerine solution instead of a solvent. Hiram Maxim patented a similar powder in England in 1889 and in the USA in 1890 by Hudson Maxim. Ballistite was patented in the United States in 1891.

The Germans adopted ballistite for naval use in 1898, calling it WPC/98. The Italian adopted it as filite, in cord instead of flake form, but realising its drawbacks changed to a formulation with nitroglycerine they called solenite. In 1891 the Russians tasked the chemist Mendeleef with finding a suitable propellant, he created nitrocellulose gelatinised by ether-alcohol, which produced more nitrogen and more uniform colloidal structure than the French use of nitro-cottons in Poudre B. He called it pyro-collodion.

Britain conducted trials on all the various types of propellant brought to their attention, but were dissatified with them all and sought something superior to all existing types. In 1889 Sir Frederick Abel, James Dewar and Dr W Kellner patented (Nos 5614 and 11,664 in the names of Abel and Dewar) a new formulation that was manufactured at the Royal Gunpowder Factory at Waltham Abbey. It entered British service in 1891 as Cordite Mark 1. Its main composition was 58% Nitro-glycerine, 37% Guncotton and 3% mineral jelly. A modified version, Cordite MD, entered service in 1901, this increased guncotton to 65% and reduced nitro-glycerine to 30%, this change reduced the combustion temperature and hence erosion and barrel wear. Cordite's advantages over gunpowder were reduced maximum pressure in the chamber (hence lighter breeches, etc.) but longer high pressure. Cordite could be made in any desired shape or size. The creation of cordite led to a lengthy court battle between Nobel, Maxim, and another inventor over alleged British patent infringement.

The Anglo-American Explosives Company began manufacturing its shotgun powder in Oakland, New Jersey in 1890. DuPont began producing guncotton at Carneys Point Township, New Jersey in 1891. Charles E. Munroe of the Naval Torpedo Station in Newport, Rhode Island patented a formulation of guncotton colloided with nitrobenzene, called Indurite, in 1891. Several United States firms began producing smokeless powder when Winchester Repeating Arms Company started loading sporting cartridges with Explosives Company powder in 1893. California Powder Works began producing a mixture of nitroglycerine and nitrocellulose with ammonium picrate as Peyton Powder, Leonard Smokeless Powder Company began producing nitroglycerine-nitrocellulose Ruby powders, Laflin & Rand negotiated a license to produce Ballistite, and DuPont started producing smokeless shotgun powder. The United States Army evaluated 25 varieties of smokeless powder and selected Ruby and Peyton Powders as the most suitable for use in the Krag-Jørgensen service rifle. Ruby was preferred, because tin-plating was required to protect brass cartridge cases from picric acid in the Peyton Powder. Rather than paying the required royalties for Ballistite, Laflin & Rand financed Leonard's reorganization as the American Smokeless Powder Company. United States Army Lieutenant Whistler assisted American Smokeless Powder Company factory superintendent Aspinwall in formulating an improved powder named W.A. for their efforts. W.A. smokeless powder was the standard for United States military service rifles from 1897 until 1908. In 1897 United States Navy Lieutenant John Bernadou patented a nitrocellulose powder colloided with ether-alcohol. The Navy licensed or sold patents for this formulation to DuPont and the California Powder Works while retaining manufacturing rights for the Naval Powder Factory, Indian Head, Maryland constructed in 1900. The United States Army adopted the Navy single-base formulation in 1908 and began manufacture at Picatinny Arsenal. By that time Laflin & Rand had taken over the American Powder Company to protect their investment, and Laflin & Rand had been purchased by DuPont in 1902. Upon securing a 99-year lease of the Explosives Company in 1903, DuPont enjoyed use of all significant smokeless powder patents in the United States, and was able to optimize production of smokeless powder. When government anti-trust action forced divestiture in 1912, DuPont retained the nitrocellulose smokeless powder formulations used by the United States military and released the double-base formulations used in sporting ammunition to the reorganized Hercules Powder Company. These newer propellants were more stable and thus safer to handle than Poudre B, and also more powerful.