registration fire vs firing

registration fire and firing both are nouns.

Word	Noun	Adjective	Verb	Adverb
registration fire	Yes	No	No	No
firing	Yes	No	No	No

As nouns, firing is a hypernym of registration fire; that is, firing is a word with a broader meaning than registration fire:

registration fire: fire delivered to obtain accurate data for subsequent effective engagement of targets
firing: the act of firing weapons or artillery at an enemy

Other hypernyms of registration fire include fire.

registration fire (noun)	firing (noun)
fire delivered to obtain accurate data for subsequent effective engagement of targets	the act of setting something on fire
	the termination of someone's employment (leaving them free to depart)
	the act of discharging a gun
	the act of firing weapons or artillery at an enemy