Not exactly a duel, but....

In August, 1917, in a town in SE Texas, a bad guy named Francisco Lopez got drunk and went around shooting out windows and lights, generally raising hell. The town marshal, named (I believe) Whitman, went out to stop the shooting. A crowd followed the marshal, who was a low-key kid of guy and who was more and more worried about someone in the crowd getting hurt by Lopez if there was shooting.

The marshal stopped around 15 feet from Lopez and told him to drop the gun, that he was under arrest. Lopez fired two shots at the marshal, missing with both but realizing the marshal's fears that bystanders would get hurt.

The marshal reluctantly drew and fired, so close to Lopez's firing that bystanders thought that they'd heard just one shot. Lopez grabbed his hand and dropped his gun like he'd been electrocuted. The marshal cuffed him and hauled him off to jail, not a mark on him.

Lopez's revolver was retrieved. No, the marshal did not shoot it out of his hand. No, he didn't shoot the cylinder out of the gun. Examination found that the marshal's bullet had entered the barrel of Lopez's gun BEFORE Lopez's third bullet could clear the barrel. This was shown to be the case when the gun was disassembled and the bulge in the barrel examined.

Probably the last of the old-time, rarely happening, Olde Weste gunfights. I wouldn't bet money on this happening again....