What is "master gunnery sergeants"

Usage examples of "master gunnery sergeants".

And three times Gunny Stecker had handed him money once ninety dollarswhich the Gunny said was his fair share of what he had taken away from visiting master gunnery sergeants and sergeants major who also had an unfounded faith in the all-around superiority of the Springfield, and who were foolish enough to put their money where their mouths were.

But he was polite, and recognized that Master Gunnery Sergeants were busy men, and that he appreciated this one giving him a little bit of his time.

There were very few Master Gunnery Sergeants of Fleet Marines, so it was not the usual thing for him to settle in with his peer group at cocktail hour and talk shop.