▁about ▁ ▁in ▁dry ▁air ▁at ▁ ▁— ▁and ▁thus ▁can ▁travel ▁a ▁substantial ▁distance ▁to ▁a ▁target ▁before ▁a ▁nearby ▁observer ▁he ars ▁the ▁sound ▁of ▁the ▁shot . ▁The ▁sound ▁of ▁gun fire ▁( i . e . ▁the ▁m uzz le ▁report ) ▁is ▁often ▁accompanied ▁with ▁a ▁loud ▁b ull wh ip - like ▁crack ▁as ▁the ▁su person ic ▁bullet ▁pier ces ▁through ▁the ▁air ▁creating ▁a ▁son ic ▁bo om . ▁Bul let ▁spe eds ▁at ▁various ▁stages ▁of ▁flight ▁depend ▁on ▁intr insic ▁factors ▁such ▁as ▁its ▁section al ▁density , ▁aer od ynamic ▁profile ▁and ▁ball istic ▁coefficient , ▁and ▁extr insic ▁factors ▁such ▁as ▁bar ometric ▁pressure , ▁hum id ity , ▁air ▁temperature ▁and ▁wind ▁speed . ▁Sub son ic ▁cart rid ges ▁fire ▁bul lets ▁slower ▁than ▁the ▁speed ▁of ▁sound ▁so ▁there ▁is ▁no ▁son ic ▁bo om . ▁This ▁means ▁that ▁a ▁sub son ic ▁cart ridge , ▁such ▁as ▁. 4 5 ▁A CP , ▁can ▁be ▁substantial ly ▁qui eter ▁than ▁a ▁su person ic ▁cart ridge ▁such ▁as ▁the ▁. 2 2 3 ▁Rem ington , ▁even ▁without ▁the ▁use ▁of ▁a ▁suppress or . ▁ ▁Bul lets ▁do ▁not ▁normally ▁contain ▁explos ives , ▁but ▁damage ▁the ▁intended ▁target ▁by ▁transfer ring ▁kin etic ▁energy ▁upon ▁impact ▁and ▁pen etr ation ▁( see ▁terminal ▁ball istics ). ▁ ▁History ▁ ▁While ▁the ▁first ▁recorded ▁use ▁of ▁gun pow der ▁in ▁Europe ▁was ▁in ▁ 1 2