Blocks assault rifles

In front of Bianca knelt a half-dozen men in plain suits that bulged in odd places. They held guns in their hands. Great big guns. Some kind of assault weapons, I thought. Their eyes looked a little vague, like they'd only been allowed to see some of what was in the room. Just as well.
I looked back at them and leaned on my staff. And I laughed. It came out a wheezing cackle, that echoed around the great hall, and caused the vampires to stir restlessly.
Bianca let her lips curve into a slow smile. "And what do you find so amusing, my pet?"
I smiled back. There was nothing friendly in it. "All of this. For a guy with two sticks and a pair of yellow ducky boxer shorts, you must think I'm a real dangerous man."
"As a matter of fact, I do," Bianca said. "Were I you, I would consider it flattery."
"Would you?" I asked.
Bianca let her smile widen. "Oh. Oh, yes. Gentlemen," she said, to the men with guns. "Fire."

Grave Peril Chapter 37, Page 417-418


I lifted my left hand before me, pouring energy into the shield bracelet, and shouted, "Riflettum!"
The guns roared with fire and thunder. Sparks showered off of a barrier less than six inches away from my hand. The bracelet grew warm as the security men poured a hail of gunfire at me. It stopped, just short, and bullets shot aside, chewing through the expensive woodwork and bouncing wildly around the room. One of the vampires let out a yowl and dropped from the wall to splat on the ground like a fat bug. One of the security men's guns suddenly jumped and twisted, and he cried out in pain, reeling back, blood streaming from his hands and the ruins of his face.
Technology doesn't tend to work too well around magic. Including the feeding mechanisms of automatic weapons.
Two of the guns jammed before dumping their full clips, and the others fell silent, spent. I still stood, one hand extended. Bullets lay all over the floor in front of me, misshapen slugs of lead. The security men stared, and stumbled away from me, behind Bianca and the vampires, and out the door. I don't blame them. If all I had was a gun, and it had just been that useless, I would run, too.

Grave Peril Chapter 38, Page 419