163 
SHORT NOTES ON THE 13-PR. M.L. GUN. 
BY 
MAJOR S. J. NICHOLSON, R.H.A. 
As the new field gun lately issued for trial differs in many points 
from any system hitherto adopted in the service, it is hoped that the 
following short notes may not be uninteresting to those officers who 
have not had an opportunity of seeing it, or the official Handbook 
containing its description. It is not intended to give a detailed 
account, but to state as briefly as possible the main points of 
difference. 
The Gun. 
Total length 
Weight, average . 
Bore ... 
( Calibre. 
\ Length.. 
.... 3*0ins. 
.... 7-0ft. 
Chamber 
C Diameter ... 
\ Length. 
Rifling , 
modern 
£ Length.. 
( number. 
.... 10 
ypolygroove 
{Grooves ... 
< depth . 
( width . ... 
.05 in. 
.... '509in. 
Vent from end of bore . 
.... 7 ins. 
Dimensions. 
An enlarged powder-chamber is given, “ with a view to obtain The bore, 
increased muzzle velocity, and therefore a longer range, a lower 
trajectory, and greater energy than existed in any previous service 
field gun, without increasing the corresponding strain upon the piece.'’* 
The diameter of the cartridge being slightly under 3 ins., it has, when 
in the powder-chamber, a certain air-space round it; thus each lb. of 
powder has 35*3 cubic ins. in which to burn, as compared with the 
26 cubic ins. of the present system. This is expressed by saying that 
the density of the charge is 35'3 cubic ins. to the lb. It is this 
