Some are made different than others. I've had 3 kinds.
One wasn't a cinch bolt at all, but rather two screws, one on each side of the carb neck that went into threaded holes on the carb neck. Kind of lame... doesn't make for clean air flow, but it was a cheap engine.
Another was like what you have. Two metal peices, one threaded, one not, the screw pinched them together and pinched the carb neck in the process.
The third was a solid shaft with a threaded end on it and a nut. The shaft had a half moon cut out of the center of it which when centered, would allow the carb to drop in. When you tightened the nut, it would pull one side of the half moon into the carb neck and cut into it a bit while pinching it.
I like the second one best. If the screw gets worn, you can replace it. Also, it pinches from both sides for a good hold.