Cordite Service Cartridges.
Velocity 2,010 F.S.
Pressure 15.67 tons.
Five rounds from the Service axite and Service cordite were placed in an oven and heated to a temperature of 110 deg. F. for one hour, and were then fired for pressure. The following results were obtained:—
Axite. Cordite. Before heating 15.76 tons per sq. in. 15.67 tons per sq. in. After " 16.73 " " 17.21 " " _____ _____
Increase .97 = 6.1% 1.54 = 9.8%
Before heating 2,150 F.S. 2,030 F.S.
After " 2,180 " 2,090 "
Increase 30 F.S. = 1-1/2% 60.0 F.S. = 3%
In order to show the accuracy given by axite, seven rounds were fired from a machine rest at a target fixed at 100 yards from a rifle. Six of the seven shots could be covered by a penny piece, the other being just outside. In order to ascertain the relative heat imparted to a rifle by the explosion of axite and cordite, ten rounds each of axite and cordite cartridges were fired from a .303 rifle, at intervals of ten seconds, the temperature of the rifle barrel being taken before and after each series:—
THE RISE IN TEMPERATURE OF THE RIFLE BARREL
With axite was 71 deg. F.
With cordite was 89 deg. F.
Difference in favour of axite 18 deg. F. = 20.2%
The lubricating action of axite is shown by the fact that a series of cordite cartridges fired from a .303 rifle in the ordinary way, followed by a second series, the barrel being lubricated between each shot by firing an axite cartridge alternately with the cordite cartridge. The mean velocity of the first series of cordite cartridges was 1,974 ft. per second; the mean velocity of the second series was 2,071 ft. per second; the increased velocity due to the lubricating effect of axite therefore was 97 ft. per second. This powder, it is evident, has very many very excellent qualities, and considerable advantages over cordite. It is understood that axite is at present under the consideration of the British Government for use as the Service powder.
Ballistite.—Nobel’s powder, known as ballistite, originally consisted of a camphorated blasting gelatine, and was made of 10 parts of camphor in 100 parts of nitro-glycerine, to which 200 parts of benzol were then added, and 50 parts of nitro-cotton (soluble) were then steeped in this mixture, which was then heated to evaporate off the benzol, and the resulting compound afterwards passed between steam-heated rollers, and formed into sheets, which were then finally cut up into small squares or other shapes as convenient.