Is this Senator Dianne Feinstein threatening to shoot anyone who does vote yes?

No, this is Senator Dianne Feinstein showing us an assault rifle.

This was posted on Hotair.
http://hotair.com/archives/2013/01/26/of-course-feinsteins-assault-weapons-ban-exempts-government-officials/

Of course: Feinstein’s assault weapons ban exempts government officials

http://hotair.com/archives/2013/01/26/of-course-feinsteins-assault-weapons-ban-exempts-government-officials/