390 
MINUTES OF PROCEEDINGS OF 
Description of the Guns. 
3. The gnus are muzzle-loading. They have solid steel tubes three 
inches thick, a solid forged breech piece, and external strengthening coils. 
Their weight averages 149 cwt. and the length of bore is 10 ft. 6 in. 
Cammed's steel is used in Scott's, Lancaster's, and the Jeffery and Britten 
guns, and Birth's steel in the other. They are vented 5*75 in. from the end 
of the bore, this being the position to give the greatest initial velocity with 
a charge of 20 lbs. 
Commander Scott's gun is rifled in five grooves, which are shallower on 
the loading side than on the driving side. The surface of the ribs on the 
shot and the bottom of the grooves in the gun are struck with the same 
radius, by which, in combination with the curves he has chosen for the 
driving side, Commander Scott hopes to attain a perfect centering for his 
shot. The rifling has a spiral of one turn in 294 in. 
Mr Lancaster's gun is oval bored, the major-axis being 7*60 in., and 
minor-axis, 7*00 in. The rifling makes one turn in 360 inches. 
The gun provided for Messrs Jeffery and Britten has thirteen grooves, 
each 0T0" in depth and of the circumference in width, or 0*846 in. The 
rifling makes one turn in 805 inches. 
The Trench gun is rifled in three grooves 0*25" deep and 2*02" wide. The 
rifling begins in a straight line, and increases gradually until it leaves the 
bore with an inclination of one turn in 259 inches. 
Description of Carriages, fyc. 
4. The guns were mounted on wooden garrison carriages with traversing 
platforms, working at first on raised racers, but the spindles of the rollers 
proving too weak, the platforms were subsequently placed upon the ground. 
The platforms were inclined at an angle of 4° 36' to 5° and no compressors 
were used. 
1st supply 
5. Description of Projectiles. 
( weight, 110 lbs. ± 2 lbs. 
C rTTU S * i f over body, 0*05" ± 0- 
(.soM shot) l windage j oyer ^ 0 . 03 „ ± 
02 ". 
01 ". 
2nd supply 
(shot hollowed 
at base) 
weight, 100 lbs. -4- 2 lbs. 
( wei 
; wi 
* ( over body, 0D8" ± 0*02". 
n a & e | over studs, 0*05" ± 0-01". 
These latter shot were of the same length as the first supply, but reduced 
in weight by boring out at the base. 
weight, 100 lbs. ± 2 lbs. 
over body, 0-08" ± 0’02". 
over studs, 0’05" ± 0*01". 
3rd supply 
(solid shot) 
wi 
ndage | 
The first supply were ordered with a smaller windage than that which the 
Committee consider it necessary to allow for service shot, in order that the 
very best shooting qualities of the guns might be developed. 
