▁tap ering ▁towards ▁the ▁rear , ▁typical ▁of ▁mort ars ▁of ▁the ▁day . ▁This ▁was ▁necess itated ▁by ▁the ▁need ▁to ▁minim ise ▁the ▁gun ' s ▁weight ▁while ▁still ▁allowing ▁it ▁to ▁fire ▁a ▁relatively ▁heavy ▁shell ▁: ▁it ▁ens ured ▁that ▁the ▁thick est ▁amount ▁of ▁metal ▁surrounded ▁the ▁point ▁of ▁maximum ▁pressure ▁on ▁firing , ▁at ▁the ▁rear ▁of ▁the ▁chamber . ▁However , ▁mort ars ▁fired ▁at ▁high ▁elev ations , ▁allowing ▁the ▁pow der ▁charge ▁to ▁naturally ▁seat ▁into ▁the ▁con ed ▁rear ▁end ▁of ▁the ▁chamber , ▁whereas ▁guns ▁such ▁as ▁this ▁fired ▁on ▁a ▁relatively ▁flat ▁traject ory , ▁leading ▁to ▁the ▁pow der ▁charge ▁sitting ▁on ▁the ▁bottom ▁of ▁the ▁chamber . ▁Hence ▁in ▁sea ▁service ▁using ▁smaller ▁" redu ced " ▁charges ▁such ▁as ▁in ▁short - range ▁actions ▁this ▁slow ed ▁the ▁rate ▁of ▁fire ▁as ▁pre ca utions ▁had ▁to ▁be ▁taken ▁to ▁ensure ▁that ▁the ▁pow der ▁charge ▁remained ▁correctly ▁position ed ▁within ▁the ▁chamber ▁until ▁firing , ▁to ▁avoid ▁a ▁mis fire . ▁ ▁Dep loyment ▁The ▁early ▁ 6 - foot ▁ 8 ½ ▁in ch ▁ 5 0 - c wt ▁version ▁was ▁de emed ▁" to o ▁light ▁and ▁short ▁for ▁arm ament ▁of ▁great ▁ships ▁of ▁war " ▁and ▁the ▁ 9 - foot ▁ 6 5 ▁c wt ▁version ▁of ▁ 1 8 3 8 ▁was ▁the ▁model ▁typically ▁deployed ▁on ▁British ▁war ships ▁" of ▁all ▁rates ▁and ▁classes ". ▁ ▁They ▁were