Show Progress in Artillery Work The power of great guns hag been developed to an extent hitherto hith-erto unprecedented in the course of experiments which have taken place at the Royal ArdeG al prool butts this week and were continued contin-ued yesterday Of late the attention of artillerists has been directed to the air spacing of cartridges aa to the probable secret of high velocities and some of the private manufac turers have devised I methods of mtroJocing the air and regulating its precise quantity which methods n they have jealously guarded against imitations At the Royal Gun Factories however the Super intendent Colonel Maitland R A has taken a new departure by giving up aIr spacing as an unprofitable un-profitable experiment and trying another system Having found bv repeated trials the description of slow burning powder best adap edo ed-o his requirements he has designed ft contrivance for retaining it in the chamber of the gun until the powder ia i sufficiently fired to let up a pressure of about two tons pr square inch upon the I base of the shot which then starts at a pound the speed of which is i accelerated by the pursuit cf the powder gases until it leaves the muzzle The retention of the shot is accomplished by R ring of metal fixed around it near the base and so regulated as to size that it will when placed in the breach be a trifle larger than the bore through I which it has to pass According to the resistance which it affords will be the period of retention It has been demonstrated by experiments with fired gunpowder that in avery a-very strong vessel the powder maybe may-be ignited and converted into gas but held under subjection for an unlimited time The retention ring is made of finch strength that it will surrender at a given pressure pres-sure and the requisite condition for the attainment of maximum velocities thus appear to have been realized With the 104mcn gun a 462 pound shot has been fired at a muzzle velocity of 2215 feet per second the equivalent of which in energy is 500foot tone but as the powder charge was somewhat in excess of the service allowance it is fair to reduce the velocity by 100 feet It will even then be far in advance of the speed attained under former conditions The improvement improve-ment has had a stronger illustration in a competitive trial between the two experimental 45ton gunsthat of Elswick mahufacture with the air spaced chamber and that of Woolwich with the retention ring The former with 350 pounds of powder rather above its service < charge discharged a 700pount projectile at a velocity of 1900 feet per second j the latter crammed with 400 pounds of powder and the same shot recorded a speed of 2120 feet These figures represent in energy respectively 17500 and 20890 ton per foot and the advantage in an attack upon armor plates may be assumed in the same proportion The discovery has created great satisfaction satisfac-tion in toe Government Department and is expected to lead to even more important results London Daily Ncios |