I'll check it.
3 seconds sound clip from the The Green Berets (1968) movie soundboard.
You can hear this line at 01:33:36 in the Blu-ray version of the movie.
Quote context
[...]
- He's pretty bad, sir, but still alive.
- See if that .50's operational.
- Fall back! Fall back! Fall back!
- Swing her around 180 degrees.
- Give them 4 H.E. Maximum elevation and destroy the tube.
[...]