| Show the life of big guns with the invention ot of smokeless cs powder for use in the big guns ot of warships and comsh coa defenses ci a problem presented itself to ordnance officers which was unknown to their sors bora ot the diya of 0 black powder arid anil smoothbore guns the problem pi is the prolongation of 0 the life of the guns all modern artillery la Is rifled that is IB each gun has a series of aspli at grI grooves DOVeS cut on its interior surface the grooves impact it a spin to the projectile as it Is foicey fibia the guu gull and the effect la Is to keep the point headed for ward lly by this means its range re ac curacy and penetration are enormous ly increased the gi gibat eat value ot of smokeless powder Is the increased ve lacity which it gives to the shell but velocity Is attained at the expense ot of a increase Inci ease of temperature of the burning gases the high tern pera ture in erodes or bums out the metal of the gun itself so that the rifling lifting at the bierch Is soon destroyed desti oyed the gun then becomes inaccurate and usdean the war nar ment of the united states has found that the big 13 10 inch gund now mount ed in roost most of the seacoast aea coast defenses ale aie good for no more than thai 60 shoal before they are woin coln out the ex pense of the guns is so great that this Is a serious mattei the striking folee foice of the projectile cannot he be reduce without It hout weakening the defenses ot of the co chantly antly but the aar it thinks it has found a way out of the alfi culty Stil stalking king force Is the prod act ot of the miss or weight ot of the projectile multiplied by bv the with which it travels in older to lengthen the life of coast defense guns guas the pressure pleasure which means speed roust must te be reduced to maintain the sam earn lr arg foice accordingly the mass of tho the shell must be increased the war do de Tart ment says youths companion compa anton Is ti to substitute 15 or 16 inch guns for the 13 inch guns now la in UP ue U P la in this way ay the same ange sad pene will be pres preserved elved and the life ot of the guns advanced from 60 shots to |
