The M870 is a pump-action shotgun of US origin. It was developed by Remington in the late 1940's in order to compete with the Winchester Model 12. It was first sold to civilians and police models soon followed. The M870 is an iconic firearm and the most produced shotgun in the world with over 10 million produced. Over the years the design has been updated to suit the demands of law enforcement and military operators.
The M870 is based on the earlier Remington Model 31, but is a more rugged and more reliable design. The M870 is a fairly conventional pump action shotgun with a tubular magazine below the barrel and a conventional grip. The police models were at first fitted with a wooden stock and slider. This later changed to a black polymer furniture. Over time the tactical models have been vastly improved and are currently available with pistol grip, retractable stock and accessory and sight rails.
The M870 fires 12 ga shotgun shells with a length of 2.75 or 3 inch. The standard magazine capacity is 5 rounds but many tactical models feature magazine extensions. The M870 is a pump action shotgun and therefore has a limited rate of fire. It is known to be very reliable and has the ability to fire non lethal rounds. Models with rifled barrels for firing slugs are also available.