Remington 870 Marine Magnum

Remington Arms Company (RemArms) · Shotgun · In Production · 1992

Also known as: 870 Marine Magnum, 870 SPS Marine Magnum, Marine 870, R25012

Overview

The Remington 870 Marine Magnum is a corrosion-resistant variant of the iconic Remington 870 pump-action shotgun, purpose-built for harsh saltwater and high-humidity environments. Every metal surface, including the inside of the barrel and receiver, is plated with electroless nickel to resist the relentless attack of salt spray, moisture, and brine that destroys conventionally finished firearms. The Marine Magnum features a 18.5-inch cylinder-choked barrel chambered for both 2-3/4-inch and 3-inch 12-gauge shells, a 6-round extended magazine tube, a synthetic stock with aggressive checkering for positive control with wet hands, and a padded Cordura sling for comfortable carry. It is the shotgun of choice for boat owners, coastal law enforcement, anti-piracy detachments, and anyone who needs the proven 870 platform to survive in environments where standard blued or parkerized finishes would be eaten alive.

Specifications

Weight (empty)3402 g (120.0 oz)
Overall Length978 mm (38.50")
Barrel Length470 mm (18.50")
Action TypePump Action
Firing MechanismHammer Fired
Trigger TypeSingle Stage
Magazine Capacity6 rounds
Magazine TypeTube
Effective Range40 m (44 yd)
Barrel RiflingNone
Frame MaterialSteel
Barrel MaterialSteel
Stock MaterialPolymer
FinishElectroless Nickel

Calibers

Features

Variants

Base model

Remington-870

Service history

Operators

Production

Production years: 1992-present

Specific Marine Magnum production numbers are not published; the broader 870 family has exceeded 13 million units since 1950

Origin

Country of origin: United States

Designer: L. Ray Crittendon (base 870 design)

Notes

The Marine Magnum was introduced by Remington in the early 1990s as a dedicated marine variant, replacing earlier nickel-plated models. The electroless nickel process deposits a uniform coating on every surface including bore interiors, providing far better corrosion resistance than chrome plating or stainless steel for harsh marine use. Remington also offers a Police Marine Magnum (R25047) with rifle sights, +2 magazine extension, and 7-round capacity for law enforcement applications, and a Tac-14 Marine Magnum firearm (non-NFA) with a 14-inch barrel and Raptor pistol grip. Production was relocated from Ilion, New York to LaGrange, Georgia in 2024 by RemArms following Remington's 2020 bankruptcy.

Background

The Marine Magnum's electroless nickel finish is so thorough that it coats the inside of the barrel and the inside of the receiver, parts most owners will never see; the process dunks the entire shotgun in a chemical bath that bonds nickel to every molecule of exposed steel without electricity, producing a finish hard enough to survive years of salt-spray service that would rust a conventional 870 to scrap.