Mossberg 590 was developed by O. F. Mossberg & sons company in the mid-1970s as a "mil-spec" (adopted for US Military) modification of the model 500 shotgun. "Militarization" include strenghtening of the receiver and other parts, installation of the vented heatshield around the barrel, bayonet lug and extended magazine.Technically, m590 is the same as m500; Manually operated, pump-action smoothbore shotgun. It is available with polymer stock, top-folding stocks or with "Cruiser" pistol grips. Sights are ghost ring or conventional rifle-type.
Mossberg 590 is ectremely rugged and reliable gun. It is adopted by US Marine Corps and by many Police depts and Law enforcement agencies across the USA.
Mossberg M590 pistol grip "Cruiser"
 
       
  Mossberg 500, along with Remington 870 and Winchester 1300, is one of the most poular and versatile USA-made pump action shotguns.
Mossberg 500 is magazine feed, manually operated (pump action) smoothbore gun. Bolt carrier is operated via two action bars, chamber locking is achieved via tilting breechblock (bolt) into the barrel extension. Safety is located at the tang of the receiver and is fully ambidextrous. Receiver is made from aluminium alloys. Barrels are interchangeable without tools.

-(Shortened and/or modified version of the article at world.guns.ru)

 
Mossberg M590 without the ironsights
       
  GAME DATA: M590

The M590 is a good pump-action shotgun (hell, it's the only pump-action shotgun in the game). It has a very good power and hitting your target can't be any easier. On the other hand, like with all shotguns, the gun is very inaccurate over long distances and doesn't carry much ammo. You'll encounter the M590 mostly in urban (Triads) and jungle (US Marines) warfare.

   
Name: Mossberg M590 / M590  
Slot: 3, shotguns  
Caliber: 12 gauge  
Capacity: 8 shells  
Firemodes: Pump-action  
Accuracy: Poor  
   
   
   
 
M590 pictured from the botton with shells

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