弾頭 is read as だんとう (dantou) and means warhead.
だんとう
dantou
かくだんとう
nuclear warhead
げんしだんとう
atomic warhead
たま
ball (i.e. a testicle)
だんあつ
oppression
はずむ
to be stimulated
はじき
repellence
だんりょく
elasticity
だんどう
ballistic
だんやく
ammunition
はずみ
bounce
はじく
to repel
ひく
to play (a stringed or keyboard instrument)