elt ▁due ▁to ▁hot ▁g ases ▁behind ▁and ▁fr iction ▁with ▁the ▁bore . ▁Because ▁co pper ▁has ▁a ▁higher ▁mel ting ▁point , ▁and ▁greater ▁specific ▁heat ▁capacity ▁and ▁hard ness , ▁co pper - jack et ed ▁bul lets ▁allow ▁greater ▁m uzz le ▁veloc ities . ▁ ▁European ▁adv ances ▁in ▁aer od ynam ics ▁led ▁to ▁the ▁pointed ▁sp itzer ▁bullet . ▁By ▁the ▁beginning ▁of ▁the ▁tw enti eth ▁century , ▁most ▁world ▁arm ies ▁had ▁begun ▁to ▁transition ▁to ▁sp itzer ▁bul lets . ▁These ▁bul lets ▁fle w ▁for ▁greater ▁distances ▁more ▁accur ately ▁and ▁carried ▁more ▁energy ▁with ▁them . ▁Sp itzer ▁bul lets ▁combined ▁with ▁machine ▁guns ▁greatly ▁increased ▁the ▁le th ality ▁of ▁the ▁battle field . ▁ ▁The ▁latest ▁adv ancement ▁in ▁bullet ▁shape ▁was ▁the ▁boat ▁tail , ▁a ▁stream lined ▁base ▁for ▁sp itzer ▁bul lets . ▁The ▁vac u um ▁created ▁as ▁air ▁moving ▁at ▁high ▁speed ▁passes ▁over ▁the ▁end ▁of ▁a ▁bullet ▁slow s ▁the ▁project ile . ▁The ▁stream lined ▁boat ▁tail ▁design ▁reduces ▁this ▁form ▁drag ▁by ▁allowing ▁the ▁air ▁to ▁flow ▁along ▁the ▁surface ▁of ▁the ▁tap ering ▁end . ▁The ▁resulting ▁aer od ynamic ▁advantage ▁is ▁currently ▁seen ▁as ▁the ▁optim um ▁shape ▁for ▁rif le ▁technology . ▁The ▁first ▁combination ▁sp itzer ▁and ▁boat - tail ▁bullet , ▁named ▁B alle ▁" D " ▁from ▁its ▁invent or ▁( a ▁lieutenant - col onel ▁Des ale ux ), ▁was ▁introduced ▁as ▁standard