THE ROYAL ARTILLERY INSTITUTION 
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the shot passing through the plate and not breaking up. All the other Whitworth 
steel shot (supplied at the same time) had broken up when fired at plates at 
200 yds. range, with a velocity of 1274 ft. per second. . 
Pig. 5 will convey some idea of the nature of bole made by steel projectiles, 
and also show the difference of effect between the steel and cast-iron shot. 
Nos. 644 and 685 were both 12-pr. Armstrong shot fired at a 2J" plate, with 
a charge of If lbs., but the former, which was steel, penetrated the plate, 
making a clean hole 3* l" x 3/'whilst the latter, which was cast-iron, only made 
an indent ofl’2''. 669 was a fiat-ended Armstrong 12-pr. shell, and 680 
a Whitworth projectile of the same description, fired at a 2" plate backed 
by 12" of wood; 669 burst in the wood backing, and 680 passed through 
plate and backing whole, penetrated 5' into an earth bank in rear, and did 
not burst. 
In January and May 1864, experiments were made at Shoeburyness to test 
spherical steel solid shot, made of BessemePs metal: they were fired from 
a 68-pr. S. B. gun, with service charges, at a “ Warrior ” target, at 200 yds. 
range. The result of the January experiment is thus recorded by the 
Committee: 
“ The shot were very tough, but were too soft for penetrating armour plates, for, 
although they did not break up on impact, they were considerably 4 set up.’ The 
superiority of steel over cast-iron for shot, to be used against armour plates, was 
very marked, for, whilst the penetration of the former was 4’8", the latter, fired 
under precisely similar conditions, only made an indent of T75".” 
This experiment also served to show that a 68-pr. smooth-bore gun, even 
with steel shot } is useless for attacking armour plated vessels at 200 yds. range, 
for the steel shot remained in the plate, thus serving as plugs to the holes 
they made. 
The shot which were fired in May were of different degrees of temper, and 
the result of the experiment is thus recorded :— 
“ The plate fired at, which was of excellent quality, was tested at Shoeburyness 
on the 17th March 1863, and the indent made thereon by a cast-iron spherical shot 
fired from a 68-pr. S. B. gun at 200 yds. range, with a 16 lbs. charge, was 2" deep, 
whereas with the Bessemer shot, fired under the same conditions, the smallest indent 
was 2‘6" deep, the greatest 3*8" deep, and the mean indentation of six shot was 
3'215".” The shot which made the deepest indent, viz. 3’8" was very little 
distorted, the increase in diameter being only 0‘ 24". 
