Bradley Cooper wanted to get a first hand experience of military training and so trained with the Navy SEALS as he prepared for his role in American Sniper.
Bradley Cooper in American Sniper
Cooper is set to play former SEAL Chris Kyle in the Clint Eastwood directed film, which looks at the military career of the sniper. The movie is based on his memoir.
And Cooper reveals that he got the opportunity to train with Chris' sniper partner as he got ready to take on this real-life role.
Speaking to Total Film, the actor said: "I wanted to do this story justice and that was never going to happen unless you do all the preparation you can.
"I trained with the Navy SEALs, and they were actually the same SEALs that worked directly with Chris," he explained.
"I trained with Kevin, who was Chris' sniper partner, and we had him as technical advisor on set because we wanted to get everything right.
"I was just acting but when I was looking through the (sniper) scope on set, I got this cold feeling that just ran through my body. You don't realise what these guys go through: we wanted to delve into that."
American Sniper marks the first time that Cooper has worked with filmmaker Eastwood, as he returns to the director's chair for the first time since musical Jersey Boys.
American Sniper will be the first big screen outing for Cooper in 2015, as he stars alongside Sienna Miller, Luke Grime, Kyle Gallner, and Max Charles.
Cooper has also finished worked on two untitled movies, one from John Wells and the other with Cameron Crowe. He has also been linked to a role in Joy, which would see him reunite with director David O.Russell and Jennifer Lawrence.
American Sniper is released 16th January.
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