bell ringer vs bull's eye

bell ringer and bull's eye both are nouns.

Word	Noun	Adjective	Verb	Adverb
bell ringer	Yes	No	No	No
bull's eye	Yes	No	No	No

As nouns, bell ringer and bull's eye are synonyms defined as:

bell ringer and bull's eye: something that exactly succeeds in achieving its goal

Other synonyms of bell ringer include home run, mark.

bell ringer (noun)	bull's eye (noun)
something that exactly succeeds in achieving its goal	in target shooting: a score made by hitting the center of the target
someone who plays musical handbells	something that exactly succeeds in achieving its goal
a person who rings church bells (as for summoning the congregation)	the center of a target