At the time of the signing of the armistice there was on hand approximately 200,000,000 pounds of smokeless powder.
It early became evident that the supply of cellulose, even though all available sources of supply were utilized to the utmost, would nevertheless be insufficient to meet our vast production program. For years it had been rumored that the Germans in the manufacture of their smokeless powder had been using, with great success, cellulose produced from wood pulp. Following out this idea, experimental work was undertaken in an effort to develop cellulose that could be produced from wood pulp in suitable physical form for nitration and which would meet the chemical requirements.
In the southern and southwestern portions of the United States there are large tracts of land from which timber has been removed and there are also vast acreages of swamp lands. Processes developed by the Ordnance Department had in view the idea of taking as much of these lands as possible for farming and reforesting and utilizing the tree stumps thereon. These stumps contained quantities of turpentine and resin that could be recovered and the resultant pulp after proper treatment could be prepared in suitable form as cellulose for nitration purposes.
The question of black powder, while an important one, did not present many difficulties excepting one, the necessary supply of potassium nitrate. This was because Germany was the principal source of the potash. It was thought that sodium nitrate might possibly have to be used as a substitute. Experimental work along these lines indicated that by using certain precautions, this substitution, if necessary, could be made, although it was never adopted.
Black powder of all grades for military purposes was being produced at the rate of 840,000 pounds a month, at a cost of 25 cents a pound, at the time the armistice was signed. At that time there was on hand 6,850,000 pounds of black powder.
If the war had continued the United States could have produced during the year 1919 more than 1,000,000,000 pounds of smokeless powder. Two-thirds of this would have been available for our overseas forces and the balance would have gone to the allied governments. This rate of production would have amounted to about seven times the quantity of explosives normally manufactured in peace times.
LOADING THE PROPELLANTS.
In addition to solving the problem of producing a sufficient quantity of propellant powder there was also the problem, just as important, of assembling this powder into fixed ammunition, or loading it into bags. The Frankford Arsenal and commercial cartridge factories, after expansion, were enabled to take care of the expanded small-arms program. But it became necessary for the Government to erect and operate several great bag-loading plants. These were located at Woodbury, N.J., Tullytown, Pa., and Seven Pines, Va.
The ordinary cartridge fired from the rifle is familiar to most people. The projectile is fitted into the metal case in which the explosive force is contained. Projectiles for big guns are made along similar lines, until the 4.7-inch gun is reached. Up to and including guns of this caliber the projectile is fired with what is known as fixed ammunition—that is to say, the shell itself is fixed into a metal container which holds the powder.
Guns above the caliber of 4.7 inches, however, are fired with unfixed ammunition—that is, the powder is loaded in silk bags, the projectile placed in the gun, and a number of bags, depending upon the size of the charge necessary, put into the breach of the gun behind the projectile. The powder is then ignited and the big shell ejected by the gases generated.