<P> The Remington 870 was the fourth major design in a series of Remington pump shotguns . John Pedersen designed the fragile Remington Model 10 (and later the improved Remington Model 29). John Browning designed the Remington Model 17 (which was later adapted by Ithaca into the Ithaca 37), which served as the basis for the Remington 31 . The Model 31 was well liked, but struggled for sales in the shadow of the Winchester Model 12 . Remington sought to correct that in 1951 by introducing a modern, streamlined, rugged, reliable, and relatively inexpensive shotgun--the 870 . </P> <P> Sales of the 870 have been steady . They reached two million guns by 1973 (ten times the number of Model 31 shotguns it replaced). As of 1983, the 870 held the record for best - selling shotgun in history with three million sold . By 1996, spurred by sales of the basic "Express" models, which were added as a lower - cost alternative to the original Wingmaster line, sales topped seven million guns . On April 13, 2009, the ten millionth Model 870 was produced . </P> <P> The 870 features a bottom - loading, side ejecting receiver, tubular magazine under the barrel, dual action bars, internal hammer, and a bolt which locks into an extension in the barrel . The action, receiver, fire control group, safety catch and slide release catch of the Remington Model 870 shotgun are similar to those used on the Remington Model 7600 series pump - action centerfire rifles and carbines . The basic fire control group design was first used in the automatic 11--48 . Twelve gauge stocks will also interchange on the older 12 - gauge - sized 20 - gauge receivers, although modification is needed to fit the smaller sized 20 - gauge receivers employed since the late 1970s . Several parts of the 870 will interchange with the semi-automatic Remington 1100 and 11--87 . </P> <P> The original 870 models were offered with fixed chokes . In 1986 Remington introduced the new Remington "Rem Choke" system of screw - in chokes (also fitted to Remington model 1100 auto - loading shotguns at the same time). Initially, the Rem Chokes were offered only in 12 gauge in barrel lengths of 21 ", 26", and 28 ". The following year the availability was expanded to the 20 gauge and included other barrel lengths . </P>

How many rounds does a remington 870 hold
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