Especially the bigger calibers!
Vanessa Dobbs, gunner on the HH-60 Pave Hawk 7.62-mm Mini-gun.
That's Airman Vanessa Dobbs!
That photo has been around a while, if she's still wearing the uniform, active, reserve or guard, she may be a Tech Sergeant or even a crusty old Master Sergeant by now. :)
Here's a link to a larger, higher resolution image. Check out her eyes. (Same shade as my wife's, our daughters, and our granddaughters, but that's not what I mean).
Her eyes say "Don't Mess with Airman Dobbs".