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2.
1) A gun with a silencer on it.
2) A stolen or unregistered gun.
We're gonna need two dumbgats to get the job done.
by turntablist May 11, 2006
 
1.
An untraceable gun. A staggering majority of violent crimes involving firearms are committed using dumb gats. The mafia & criminals in general are not going to be deterred by gun-control laws, they will be willing and able to procure untraceable arms of their choice and use them to commit crimes irrespective of any laws.
Guido: "What you want I should do wit da gun once I shoot da poor bastard?"

Vinnie: "Drop the dumb gat and take the cannoli wit you."
by BadlyBlownFuse November 21, 2008