Why don't you try it and see?
4 seconds sound clip from the Deliverance (1972) movie soundboard.
You can hear this line at 00:42:27 in the Blu-ray version of the movie.
Quote context
[...]
- Don't say anything, just do it.
- You ever had your balls cut off, you fucking ape?
- Lord.
- Lookie there. That's sharp. I bet it'd shave a hair.
- Why don't you try it and see?
- Lord... Lord, deliver us from all...
- Pull off that little old bitty shirt there too.
- He bled.
- Them panties, take them off.
- Get up. Get up, boy. Come on, get on up there.
[...]