some vs just about

some is an adjective but just about is not an adjective.

Word	Noun	Adjective	Verb	Adverb
some	No	Yes	No	Yes
just about	No	No	No	Yes

As adverbs, some and just about are synonyms defined as:

some and just about: (of quantities) imprecise but fairly close to correct

Other synonyms of some include about, approximately, around, close to, more or less, or so, roughly.

some (adjective)	just about (adjective)
(quantifier) used with either mass nouns or plural count nouns to indicate an unspecified number or quantity
remarkable
relatively many but unspecified in number

some (adverb)	just about (adverb)
(of quantities) imprecise but fairly close to correct	(of quantities) imprecise but fairly close to correct