Well, someone could do a video showing a hunting gun (30.06 will do nicely) and an AR on same targets (watermelon, ham, whatever) and their firing rates. That would satisfy us that her claims are lies.
BUT BUT BUT - proggies would use it to to show that hunting guns are as dangerous as an AR, and so must also be banned. She is likely playing sneaky on this, respond very cautiously...
If you will remember, back around 1989, an anti-AK-47 movement was spread by the news media.
To show how dangerous these rifles were a melon was shot. It merely poked holes in the melon.
So a melon was shot with a different firearm and an exploding bullet. Great blow up of the melon.
That night on the national news, we see an AK-47s fired, then a cut to an exploding melon. No mention a different firearm or bullet used.