THE ROYAL ARTILLERY INSTITUTION. 
12 ? 
Table VIII. 
Abstract of the Besults of the Experiments made to ascertain the 
Difference in Initial Velocity between High and Low Gauge Projectiles. 
Armstrong 
12-pounder. 
No. of Rounds. | 
Charge. 
Projectile. 
Velocity 
at 
30 Yards. 
Initial 
Velocity. 
Remarks. 
Weight. 
Diameter. 
No. 224 
5 
6 
11 
8 
lbs. oz. 
1 8 
lbs. oz. 
11 9 
3*080 
3-083 
3*080 
3-085 
1184*1 
1177-2 
1184-1 
1187*8 
ft. 
1193-4 
1186*5 
1193-4 
1197*1 
| Bore washed, 
j Lubricating wads used. 
25. In the series numbered XLYIII. to LI. are given the com¬ 
parative initial velocities of the old (A) and new (Q) pattern 12-pr. 
shells, both with and without lubricating wads. 
It will be seen that while the old pattern shell has, although scarcely 
appreciable, a slightly higher initial velocity, due to the greater dia¬ 
meter at the back end, the introduction of the lubricating wads adds 
to the velocity about 15 feet. 
The effect of the greater diameter at the back end will be again 
referred to ; but it is interesting to observe that while the initial velocity 
is increased by offering, in the first instance, increased resistance to the 
motion of the projectile, it is also increased by diminishing as much as 
possible the resistance of the friction in its passage through the bore. 
The explanation of these results is too obvious to require remark. 
Table IX. 
Abstract of Experiments made to ascertain the Difference in Initial 
Velocity of old and new Pattern 12-pr. Shells, ivith and without 
Lubricating Wads. 
Armstrong 
12-pounder. 
No. of Rounds. | 
Projectile. 
V elocity 
at 
30 Yards. 
Initial 
Velocity. 
Remarks. 
Charge. 
Weight. 
Diameter. 
.a r 
"A 
© 
£ t. 
15 
14 
13 
10 
lbs. oz. 
1 8 
lbs. oz. 
11 9 
3-072 
3-085 
3-072 
3*085 
1154*2 
1157-1 
1142-0 
1140-6 
ft. 
1163-2 
1166-1 
1150*8 
1149-4 
Q pattern shell, lubricating wad. 
A „ „ „ „ 
Q „ „ bore washed. 
A „ „ „ „ 
26. The annexed table gives an abstract of the experiments made to 
compare the initial velocities of shell of the same form and weight, fired 
from rifled and smooth bored 32-prs. of 58 cwt. The ribbed shell was, 
in the first case, fired from the rifled gun. Shells of the same form, 
diameter, and weight, but with the ribs removed, were then fired from 
the rifled gun, and finally similar shells were fired from a smooth bored 
32-pr. 
The velocities in these three cases were respectively 1224*5, 1135*3, 
and 1201*7 ft. per second. The great difference in velocity in the 
