slang vs slam-bang

slang is a noun but slam-bang is not a noun.

Word	Noun	Adjective	Verb	Adverb
slang	Yes	No	Yes	No
slam-bang	No	Yes	No	Yes

slang (noun)	slam-bang (noun)
a characteristic language of a particular group (as among thieves)
informal language consisting of words and expressions that are not considered appropriate for formal occasions; often vituperative or vulgar

slang (adjective)	slam-bang (adjective)
	violent and sudden and noisy

slang (adverb)	slam-bang (adverb)
	in a violent or sudden or noisy manner
	with heedless speed
	in a careless or reckless manner