Actor R. Lee Ermey in his ranch outside of Los Angeles. Angel Canales/ABC News

Los Angeles - Retired Marine Corps Gunnery Sgt. R. Lee Ermey has had a great acting career for over 35 years. Before his Hollywood career skyrocketed, Ermey, 70, was a farm boy in Kansas growing up with five other brothers.

"I grew up in a farm, so I didn't really have any playmates or friends with the exception of my brothers," he said.

Ermey's father was in the U.S. Navy and he wanted to follow in his dad's footsteps. However, Ermey ended up joining the Marine Corps after he saw one in person.

A young R. Lee Ermey riding a horse in the farm in Kansas. Courtesy R. Lee Ermey

"There's a Marine standing in full dress blues and I just looked at him and I thought 'Oh boy, hey.' If these guys were a uniform like that, they couldn't do too much work. This is something I should look into. I assumed incorrectly," he said with a smile.

He joined the Marine Corps in 1961 and said he really enjoyed his time there.

"When I went into the Marine Corps, I had all kinds of playmates, all kinds of brothers and friends. I like that aspect of it," he said.

R. Lee Ermey in full Marine uniform. Courtesy of R. Lee Ermey

When it came time to re-enlist after four years, he wasn't too enthusiastic about going back to the farm. As a result, he ended up serving honorably for 11 years.

"I thought well, 'What do I want to do? Do I want to go back to the farm or do I want to stay in the Marine Corps?'" he said.

It worked out just fine for Ermey. He went on to become a staff noncommissioned officer and served two years as a drill instructor.

"I would rather have been out fighting in the war rather than training people to fight the war but that's the way it works," he said.

Ermey was deployed once to Vietnam and retired in 1971.

"The hardest part about being retired out of the Marine Corps was to find myself standing outside the gate in San Diego with nothing but a green sea bag. The toughest part of the transition was leaving my friends behind because every friend that I had in the world was back there," he said.

Ermey was awarded an honorary promotion to Gunny in 2002. But Ermey had to reinvent and find a way to support himself.

"Whether I liked it or not I was retired but that didn't mean that I had to leave the [Marine] Corps. Supporting me was the question. I was a grunt. I was an instructor. There's no big call for grunts or drill instructors or people running up a hill to kill the bad guys in civilian life," he said.

At the same time, Vietnam War theme shows started production and Ermey took notice. He used his G.I. Bill benefits and enrolled at the University of Manila in the Philippines, where he studied drama.

Actor and Retired Marine Corps Gunnery Sgt. R. Lee Ermey (center on right) with his 1966 Marine recruits at the Marine Corps Recruit Depot in San Diego. R. Lee Ermey/U.S. Marine Corps

"I said, here's my chance. Here's the door. Here's the big door that's going to come open for me. It would get my foot inside the door to impress the appropriate people," he recalled.

The plan worked. Film Director Francis Ford Coppola was filming "Apocalypse Now" in the Philippines and cast Ermey in a featured role. From there, Ermey's career catapulted following the iconic 1987 film by film director Stanly Kubrick "Full Metal Jacket."

"When you do a really fantastic film with a great role that you're able to customize for yourself, the doors fly open. Let's face it, I was a drill instructor, I was a Marine and I am a Marine so who knows better," he said.

Ermey, who was nominated for a Golden Globe for Best Supporting Actor, has been working nonstop since and has appeared in over 120 films.

His new job is one he really enjoys - one where he gets to show his softer side. When Sportsman Channel ask Ermey to host the new reality show "Saving Private K-9? last year, he said yes. Saving Private K-9 features untold stories of military and law enforcement dogs. Each episode highlights the dogs' battlefield training, heroic accomplishments and relationships with their handlers - as well as their impact on those who have worked with them.

A scene with host R. Lee Ermey from Saving Private K9 with military dogs. Sportsman Channel

"I love reuniting the dogs with their former handlers and I want people to know that these dogs are very adoptable, extremely trained and smart," said Ermey, who has a soft spot for dogs and currently has two of his own on his ranch outside Los Angeles.

Re-airings of the show start Aug. 11 at 7 p.m. ET.

Second Tour is an ABC News digital series profiling the lives of military veterans who are doing unique things in the civilian world. For more stories, click here.

ABC News' video editor Arthur Niemynski contributed to this report.