Gunnery Sergeant Hartman (R. Lee Ermey) speech to the new Marine recruits.

“...You are not even human fucking beings. You are nothing but unorganized grabastic pieces of amphibian shit! Because I am hard, you will not like me. But the more you hate me, the more you will learn. I am hard but I am fair. There is no racial bigotry here. I do not look down on niggers, kikes, wops or greasers. Here you are all equally worthless. And my orders are to weed out all non-hackers who do not pack the gear to serve in my beloved Corps. Do you maggots understand that?”

Ermey actually served as a U.S. Marine drill instructor during the Vietnam War. Based on this experience, he ad libbed much of his dialogue in the film.

According to the trivia section of IMDB.com:

• R. Lee Ermey went to Stanley Kubrick and asked for the role of Gunnery Sgt. Hartmann. In his opinion, the actors on the set were not up to snuff. When Kubrick declined, Ermey barked an order for Kubrick to stand up when he was spoken to, and the director instinctively obeyed. Ermey got the role.

• Stanley Kubrick had nothing but praise for R. Lee Ermey's skills as a performer. Kubrick originally was going to write dialogue for Ermey's character himself, but he became so impressed with what Ermey improvised, that he decided it wasn't necessary. He just let him ad-lib, something practically unheard of for a Stanley Kubrick film. Ermey's performances were so faultless that Kubrick only needed 2-3 takes to get his scenes filmed, also extremely rare for a Kubrick film. The only instance Ermey had to film more than 2-3 takes was in the Jelly Doughnut Scene - which he claims was filmed in 37 takes, to the point his voice kept disappearing from time to time.

• To make Gunnery Sgt. Hartmann's performance and the recruits' reactions as convincing as possible, Matthew Modine, Vincent D'Onofrio, and the other actors playing recruits never met R. Lee Ermey prior to filming. Stanley Kubrick also saw to it that Ermey didn't fraternize with the actors between takes.

• R. Lee Ermey hardly blinks at all in any scene.

• According to director John Boorman, Stanley Kubrick wanted to cast Bill McKinney in the role of Gunnery Sgt. Hartman. However, Kubrick was so unsettled after viewing McKinney's performance in Deliverance (1972) that he declined to meet with him, saying he was simply too frightened at the idea of being in McKinney's presence. Kubrick then hired Tim Colceri to play Hartman. Colceri never got to play the role, as former US Marine Corps Drill Instructor R. Lee Ermey, consultant for the Marine Corps boot camp portion of the film, performed a demonstration on videotape in which he yelled obscene insults and abuse for 15 minutes without stopping, repeating himself or even flinching - despite being continuously pelted with tennis balls and oranges. Stanley Kubrick was so impressed that he cast Ermey as Hartman. Colceri was bitter but accepted Kubrick's consolation prize of a small role as a helicopter door-gunner.

• Gunnery Sergeant Hartman (R. Lee Ermey) is never seen without his cover (drill instructor hat.)