Fire Away (phrasal verb) 🔥

If you have any more questions, fire away.  I recently read this in an email. What does  

fire away mean? It simply means, go ahead and ask  your questions. So, here’s an example. Let’s say  

I am a professor and I am giving a lecture,  a presentation to my students. I might say,  

“If any questions come up during the  lecture, fire away.” But, I might say  

the opposite.” If any questions come up during  the lecture, please hold them until the end.”

Fire away.