The primary series of the Mossberg 500 shotguns are specially modified for police and military use. The have been described by some gun authors as "reloadable Claymores." (the M18A1 Claymore is a directional anti-personnel mine). The Mossberg 500 design is such as to ensure maximum reliability in use. The shotgun has twin extractors, and slide mechanism with twin guide bars that help prevent twisting or jamming during rapid operation making three aimed shots a second possible. The loading system is also 60 percent faster than any other, the shell carrier being receded in the block. However, operators looking to improve a time proven Model 500 and the first thing to be improved were its classic stock. A common fallacy with modern long guns is that they should be fired from the hip. In fact, over 80 percent of all firearms training given to Special Forces personnel involves obtaining a flash sight picture at the minimum. As a highly recognized manufacturer of shotguns with an immense following in law enforcement world, Mossberg got a wide variety of stocks and pistol grips to choose from, depending on your style preferences and the utility you need it for.