Dust Cover

A dust cover is a rifle part that attaches to the upper receiver of a semi-automatic rifle that prevents debris from entering through the ejection port into the bolt and chamber when being transported. When the first shot is fired, the dust cover drops away to allow spent cases to eject properly from the chamber and is retained on the receiver with a spring clip. The dust cover then must be manually snapped into place by the operator when firing has stopped. On modern handguns, the term “dust cover” is commonly used to describe the portion of the frame or grip module just forward of the trigger guard and below the slide. This dust cover is also often machined to include a 1913 picatinny rail  (or other proprietary rail system) to attach accessories.