▁the ▁trac er ▁path ▁leads ▁back ▁to ▁its ▁source . ▁To ▁make ▁it ▁more ▁difficult ▁for ▁an ▁enemy ▁to ▁do ▁this , ▁most ▁modern ▁trac ers ▁have ▁a ▁delay ▁element , ▁which ▁results ▁in ▁the ▁trace ▁becoming ▁visible ▁some ▁distance ▁from ▁the ▁m uzz le . ▁Depending ▁on ▁the ▁target , ▁trac er ▁bullet ▁le th ality ▁may ▁be ▁similar ▁to ▁standard ▁ball ▁am mun ition . ▁ ▁The ▁forward ▁portion ▁of ▁a ▁trac er ▁bullet ▁contains ▁a ▁substantial ▁sl ug ▁of ▁lead ▁fill er , ▁nearly ▁as ▁much ▁as ▁the ▁non - t rac er ▁ball ▁round ▁that ▁it ▁traject ory ▁matches . ▁ ▁In ▁the ▁case ▁of ▁the ▁M 1 9 6 / M 1 9 3 ▁bullet ▁set , ▁the ▁le th ality ▁differences ▁are ▁probably ▁neg lig ible ▁for ▁this ▁reason . ▁ ▁However , ▁with ▁the ▁M 8 5 6 / M 8 5 5 ▁bullet ▁set , ▁the ▁M 8 5 5 ▁ball ▁round ▁contains ▁a ▁steel ▁pen etr ator ▁tip ▁that ▁is ▁not ▁present ▁in ▁the ▁M 8 5 6 ▁trac er ▁bullet . ▁ ▁As ▁a ▁result , ▁different ▁le th ality ▁effects ▁can ▁be ▁expected ▁against ▁various ▁targets . ▁ ▁Nevertheless , ▁under ▁some ▁circumstances , ▁a ▁slight ▁de grad ation ▁in ▁le th ality ▁can ▁often ▁be ▁made ▁up ▁for ▁by ▁the ▁psych ological ▁and ▁suppress ive - fire ▁effects ▁trac er ▁bul lets ▁can ▁have ▁on ▁an ▁enemy ▁who ▁is ▁receiving ▁them . ▁▁ ▁Besides ▁gu iding ▁the ▁shoot er ' s