GUN TESTING.

Dominion, Volume 2, Issue 605, 7 September 1909, Page 5

GUN TESTING.

i ißy Tclceropli.-Spocloli CorrcsDoniloDt.l . , Chilstciiurcli, September 0. At- Fort Jervois,: I,yitc!ton, on Saturday afternoon Caplaili ltichardSbn, Chief,lnstructor ■ in vArtillerj,';'performed- ;oii" the- six-inclr. atid eight-inch,guns the series,of tests which cniistitutbtlio process, of calibration! ..- The 'handling;bf ..tlio, gun's had',to..be, deliberate,, iniifont),, and as 'scientifically ■ carried. out as possible,-'• Observations-were''made'for or, ljyjCaptairi Richardson of the wind: speed; the tonipcrattire\of''tbe^air,-: and of charges,' and thft height of the; barometer. Tho' condition of the: guus, and ammunition. was tested. Each gun was fired fife' times at a stationary targot> approximately' '4000 yards .away, and careful were: mado Of.', tho; tlmb the shell ■ occupied '-in '. flight, '.'the clistaiico of tho point of impact before;'or behind the target, and the exact, elevation, of the gun. .Incidentally, some excellent-shoot-ing, was flono. Tho. apparent;.workfeeased with tlio fifing'of the last'shot, but tins calculations still to be made are the vital- part' of tho' calibration. .Each Of the observations inojitioribd •- has its; bearing on tho final result,'and another'will enter into; the calcula-', jtions as! well. A siiiall inistrument of steel' 'containing", a little copper disc was '.placed- in the'chamber 'behind tho powder charge before each shot, - This was a '-'crusher gauge.'!.' ,U the timo.of tlio explosion tlio parts, of' the gauge arb so .compressed - by. the enormous prcssnro of the. gases, a pressure measured: ,in' ; tons on tho square inch, ' that the istrajn' cpmes 'directly: upon, the copper :'disc':'ari(l squeezes it:.. thinner.- It is carcfullv ad-,-justed, so that an, exact measurement of'its distortion gives the pressure of the gas in' the-.- By, combining-'all .tlio' data bbtaitved at tho practice, and calculating the efteot of the wear which liob talceiV place in the guns sined" they, we're built, a factor 1 can be arrived at giving the error, if any, of the guns Under given.conditiohs, and from that as. ,'a 'commencement it is •ai'comparatively; Simple rnattor to work out the'corrections for all times, and to "doctor'-', as required the' tangos given by the range-finder -before fix-, ing the elevation of tho' woapons,