This was caused by the shell slipping out of the magazine under the bolt in the receiver to bind the action, requiring rough treatment of the action or even disassembly. The 870's production for over 30 years had a design flaw whereby a user could fail to press a shell all the way into the magazine when loading - so that the shell latch did not engage the shell - which could result in tying up the gun. The following year the availability was expanded to the 20 gauge and included other barrel lengths. Initially, the Rem Chokes were offered only in 12 gauge in barrel lengths of 21", 26", and 28". 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). The original 870 models were offered with fixed chokes. Several parts of the 870, such as buttstocks and magazine tubes, will interchange with the semi-automatic Remington 1100 and 11–87. 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. The basic fire control group design was first used in the automatic 11–48. 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. It has dual action bars, internal hammer, and a bolt which locks into an extension in the barrel. The gun comes with a plug for migratory bird hunting which reduces the magazine's capacity to two rounds. The 870 features a bottom-loading, side ejecting receiver and a tubular magazine under the barrel. On April 13, 2009, the ten millionth Model 870 was produced. 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. As of 1983, the 870 held the record for the best-selling shotgun in history, with three million sold. Remington sold two million guns by 1973 (ten times the number of Model 31 shotguns it replaced). To achieve better sales, Remington produced the Model 870 in 1950, which was more modern and reliable in its construction, easy to take apart and maintain, and relatively inexpensive. Consequently, it struggled in sales compared to the Winchester Model 12. The Model 31 was marketed as the “ball-bearing repeater” and was well-received, but its many machined and handfitted parts made the gun expensive to manufacture. 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. John Pedersen designed the fragile Remington Model 10 (and later the improved Remington Model 29). The Remington 870 was the fourth major design in a series of Remington pump shotguns. It is widely used by the public for shooting sports, hunting and self-defense, as well as by law enforcement and military organizations worldwide. The Remington Model 870 is a pump-action shotgun manufactured by Remington Arms Company, LLC. Also cantilever and receiver-mounts for scopes 410 boreģ+1, 4+1, 5+1, 6+1, or 7+1 round internal tube magazine, or an external 6+1 box magazineīead, twin bead, adjustable open sights, or ghost ring (all iron sights). Pinckneyġ2 gauge, 16 gauge, 20 gauge, 28 gauge, or. The Model 121 Remington which replaced the Model 12 can handle high speed ammo for example.L.Ray Crittendon, Phillip Haskell, Ellis Hailston, G.E. Perhaps someone else that knows this gun will be along. I have no experience with the Model 6 so can't advise on it. Many of the guns of this period were not stout enough for high speed ammo. If you value your gun, I would recommend sticking to standard velocity ammo and use a more modern gun for high speed ammo. But there are known examples of bolt failure in these guns due to repeated firing of high speed ammo over a period of time. I shot high speed ammo for a little while in the first Model 12 I owned without permanent damage. Can you shoot high speed ammo in the gun? You can, but repeated use of that ammo over a period of time can lead to damage of the bolt. There isn't adequate lockup surface between bolt and the receiver to safely withstand repeated firing of high velocity ammo over a period of time without risking damage to the gun.