"Some of the earliest ammunition sent to our forces in France developed a tendency to hang fire and to misfire; and a liberal quantity of it, amounting to six months’ production of the Frankford Arsenal, was condemned and withdrawn from use. This matter was aired fully in the newspapers at the time it occurred. It developed that the faulty ammunition had been produced entirely in the Frankford Arsenal and that the cause of the trouble was the primer in the cartridge.
The primers in the ammunition manufactured at the Frankford Arsenal had given ordinarily satisfactory results in 12 years of peacetime use. The flame charge in this primer contained sulphur, potassium chlorate, and antimony sulphide. Produced under normal conditions, with plenty of time for drying, this primer was satisfactory. But sulphur when oxidized changes to an acid extremely corrosive to metal parts, and oxidized primers are liable not to function perfectly. Heat and moisture accelerate the change of sulphur to acid; and if there happens to be bromate in the potassium chlorate of the priming charge, the change is even more rapid.
An investigation of the Frankford Arsenal showed that these very elements were present. Because of the haste of production of cartridges, too much moisture had been allowed to get into the arsenal dry houses. The potassium chlorate was also found to contain appreciable quantities of bromate.
The condition was remedied by adopting another primer composition. And then, to play doubly safe, the Government specifications were amended to prevent the use of potassium chlorate containing more than 0.01 per cent of bromate.
However, this condemned ammunition was but a trifling fraction of the total output or even of the production then going on. The primers used by the various private manufacturers of ammunition functioned satisfactorily."
(America’s Munitions 1917-1918, Report of Benedict Crowell, the Assistant Secretary of War, Director of Munitions, 1919)