Ghost gun
A ghost gun is a term for a (typically) homemade or improvised firearm that lacks commercial serial numbers or a commercial firearm that has had its serial number removed, making these firearms harder to trace. The term is used mostly in the United States by gun control advocates, gun rights advocates, law enforcement, and some in the firearm industry.[1][2][3][4] In general, un-serialized guns are legal in the United States.[1] By making guns themselves, owners are usually not subject to federal or state commercial background check regulations.[5]
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