'Gunny' is short for a USMC Gunnery Sergeant, a senior non-commissioned officer rank.

https://en.wikipedia.org/wiki/Gunnery_sergeant

engineer. He served in the Vietnam War and eventually retired and went to work at one of those companies in the D.C.area that hired former military officers who had his training. I dunno if he had any "blue water" experience...

There is, or was, a rating in the navy known as a Gunner's Mate IIRC. It dates back to the old gunpowder days, and has probably been left off the list lately with the high tech nature of weaponry.

A naval officer could very reasonably be expected to have a Gunner's Mate under his command, moreso than having a somewhat senior Marine NCO serving with him.

Would make sense.

-- Mal

My brother was a gunny. At least it's a cooler-sounding rank than Sergeant First Class, which I always thought was a dumb title, especially given that it could be easily confused with First Sergeant. (By non-military, of course)

Back in the bad old days, ships had some guns crewed by Marines. I wonder if they still do?

-- Mal

so, I'd say there are those who have done the land based equivalent. I peaked at Staff Sergeant, and I worked in the air wing.