stamp collection vs stamp collecting

stamp collection and stamp collecting both are nouns.

Word	Noun	Adjective	Verb	Adverb
stamp collection	Yes	No	No	No
stamp collecting	Yes	No	No	No

As nouns, stamp collection and stamp collecting are synonyms defined as:

stamp collection and stamp collecting: the collection and study of postage stamps

Other synonyms of stamp collection include philately.

stamp collection (noun)	stamp collecting (noun)
the collection and study of postage stamps	the collection and study of postage stamps
a collection of stamps