Tomorrow at 1300 Douglas .
Hmmm. I was in the Artillery - that's "one-three-hundred hours, over".
My military training way back in the olden days stated that if you used the word over to an Arty guy , he would do it again...I could get with that.
No. The conversation would be: "one-three-hundred hours, over" with the response "one-three-hundred hours, out". The whole thing echoed to ensure accuracy.
The restricted word is "repeat". By saying "repeat, over" (and the response "repeat, out") the same firemission would be repeated. That is to say if the call for fire had been Battery 2 rounds, HE & WP in effect, on the word "REPEAT, over" the entire battery would fire another 6 rounds of HE and WP another two times at the same target.
SO, to avoid that from being misunderstood, "Say again, over" is used. (And I would always say: "Say what? over".)