The M6C pistol is a sidearm used in Halo 2 and Halo 3: ODST.
About this creation
Video on Flickr showing working features and more views: Click here
Working features: moving slide and removable magazine.
Though I do build guns with LEGO and enjoy shooter games like Halo, I do not promote the use of guns in aggressive or sickening ways. May the families and community of the victims of the tragedy at Sandy Hook Elementary School find peace.