Chances are, tha language I heard during the combat scenes are what I would say in that situation. That doesnt mean it is appropiate for a child under 18.
Back in the days before sensitivity training and all, the military was a place where cussing was done just for the fun of it as much as you could. It would be very difficult for any movie to go over the top on this.
I grew up on Marine Corps bases in the 50's and 60's. Marine Corps children were world class cussers. The enlisted Marines I was around used a cuss word in every sentence if at all possible.
When I was in the Navy in 67 to 71 it was the same way. The "F" word was required to be present at least once in each sentence.