That what you have read in the title is possibly an error in my head.

I like history movies, the old ones (Technicolor history spectacles) as well as new ones (those with copied/pasted soldiers).
I bet that you've all seen many of these filmed battles, with time of action long before firearms were invented! And of course that you have imagined yourself in those battles!

Yes, I know! Probably exciting from the couch where you're sitting! I have a cousin who gets so excited while he watches those battles that he constantly moves his hand like he's carrying a sword! And he doesn't even notice that!

If something takes us back through the time in the middle of some bloody battle, we would probably killed very quickly!

But what if I take a MACHINE GUN with me?

Honestly, I can't have fun by imagining myself in medieval (or fantasy) battle but without any fire weapon! A machine gun would probably change the history, but there would be a large radius of dead bodies around me (let's say orcs, a word "humans" in this context sounds violent) and if I have had a proper coffee on that morning, I would somehow manage to avoid arrows and spears for some time.