automatic gun vs autoloader

automatic gun and autoloader both are nouns.

Word	Noun	Adjective	Verb	Adverb
automatic gun	Yes	No	No	No
autoloader	Yes	No	No	No

As nouns, autoloader is a hypernym of automatic gun; that is, autoloader is a word with a broader meaning than automatic gun:

automatic gun: a firearm that reloads itself and keeps firing until the trigger is released
autoloader: a firearm that reloads itself

Other hypernyms of automatic gun include self-loader.

automatic gun (noun)	autoloader (noun)
a firearm that reloads itself and keeps firing until the trigger is released	a firearm that reloads itself