My friends & I used to imitate some of his lines from "The Boys In Company C" during the early '80s but it wasn't until "Full Metal Jacket" did we learn R. Lee Ermey's name.
He was outstanding in that. As the story goes, he was originally hired as an advisor but felt that the actor playing the sergeant wasn't good enough so he sent a videotape to Kubrick auditioning for the role. Supposedly, it's a non-stop 15 minute barrage of verbal abuse from Ermey, barking orders & delivering insult after insult. No pauses, no repeating himself, the whole time being pelted with oranges and tennis balls! I would love to see that tape someday.