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MINUTES OF PROCEEDINGS OF 
14. The Committee have now placed the Secretary of State in possession 
of all the material facts elicited by the comparison of cast-iron 32-prs. rifled 
on different systems, and will proceed to draw the conclusions which they 
think warranted by them. 
The systems of rifling tried may be reduced to five, viz.:— 
(1) Tor expanding lead-coated projectiles, represented by the guns of 
Messrs B. Britten, A. Jeffery, and Lynall Thomas. 
(2) Tor projectiles with ribs or projections faced with zinc, with long 
bearings—Commander Scott's, and the shunt 32-pr., which, however, it must 
be remembered, was not prepared for this competition (see § 1), and fired 
shells of a weight calculated for a wrought-iron (not a cast-iron) gun of this 
calibre. 
(3) Tor projectiles with studs or projections faced with zinc, having 
short bearings—the Trench system. 
(4) Projections not faced with zinc, with short bearings—Mr Haddan. 
(5) The oval bore. 
Mr Haddan and Commander Scott use a wad or sabot of wood or papier- 
mache, and tried a variety of patterns. Both these gentlemen lay great 
stress on an operation of centering, supposed to be secured by the form of 
the grooves, and of the bearing edges of the flange or projection on the 
projectile, and which is intended to prevent any deviation of the axis of the 
shot from that of the gun. This, however, is equally sought in the shunt 
system and the Trench system, and to judge by the accuracy of the shooting, 
appears to be more perfectly attained by them. 
15. These systems may be compared under the following heads :— 
(1) Safety and durability of the gun, which includes absence of liability 
in the projectile to jam in the bore. 
The Committee rank them in the following order :— 
1 Britten, least liable. 
5 French.* 
6 Haddan. 
7 Scott. 
8 Lancaster, most liable. 
2 Jeffery. 
3 Thomas. 
4 Shunt. 
Tor projectiles of the same weight, the same diameter, and fired with the 
same charge, the strain upon the gun may be assumed to vary directly as 
the sine of the angle of rifling, but will be in a certain degree dependent also 
on the amount of friction between the surfaces in contact; thus, it is least 
for copper rubbing on iron, and greatest for one iron substance rubbing 
on another. The relative order will be copper, zinc, lead, iron. 
* The gun rifled on the French system burst subsequently to the date of this Report, on the 
14th April, 1863, at the 107th round. 
