By: Friedrich Seiltgen
Copyright © 2025
ABOUT MOSSBERG
In 1886, Oscar Frederick Mossberg emigrated from Sweden and began work at the Iver Johnson Arms & Cycle Works in Fitchburg, Massachusetts. In 1919, he and his two sons, Harold and Iver, began O.F. Mossberg & Sons, Inc. with a dream to build durable, reliable firearms. The Mossberg legend began in a rented loft on State Street in New Haven, Connecticut, where Oscar Mossberg and his sons Iver and Harold began producing the 4-shot, .22 caliber Brownie pistol. Mossberg made approximately 37,000 Brownie pistols.
In 1947, the Model 183D bolt-action shotgun was introduced. It is the first Mossberg repeating shotgun with an adjustable choke.
In August 1962, the first Model 500 was produced. This pump-action shotgun would become legendary for its reliability and durability. In 1979, Mossberg was awarded a government contract to build the Model 500 as a combat-duty-rated pump shotgun. Every branch of the United States Military would eventually adopt it.
In 2017, the revolutionary Mossberg 590 Shockwave was introduced. This ultra-portable shotgun gave shooters a legal alternative to a short-barreled shotgun without needing a tax stamp.
In 2019, Mossberg celebrated 100 years in business. The company has remained family-owned, family-operated, and committed to offering “more gun for the money” with the most innovative, reliable firearms on the market.
THE 590 RM
With many design changes, the 590 RM combines Mossberg’s reliability with modern technology. It is the first production pump action shotgun fitted for double-stack magazines and uses an AR-style rotary safety selector.
THE RECEIVER AND INTERNALS
The noticeable differences with the receiver are the rotary-style safety selector switch and, of course, the removable magazine. Mossberg engineered the magazine with integral stabilizing ribs that engage notches on the receiver. The magazine release is ambidextrous as it is in front of the trigger guard. Other features include a top Picatinny rail for optics, an enlarged and beveled loading port with an exposed follower, non-binding twin action bars, an anti-jam elevator, dual extractors, elongated bolt release, a flat profile trigger, 2 QD cups, and Magpul MBUS 3 adjustable sights.
THE FURNITURE
The stock is a 5-position adjustable with an interchangeable recoil pad, compact forend, front M-LOK adapter with dual accessory mounting slots at 3 and 9 o’clock, and a Magpul MOE pistol grip.
THE BARREL
The barrel is 18.5 inches long with a 2.75-inch chamber and integrated heat shield that is removable.
SPECIFICATIONS
Type: Pump-Action Shotgun
Caliber: 12 Gauge
Chamber: 2 ¾ Inch
Magazine Capacity: 5, 10, 15, or 20 Rounds
Sights: Magpul MBUS 3 Adjustable Sights
Barrel Length: 18.5 Inches
Overall Length: 36.9 Inches
Length of Pull: 12 to 15.25 Inches
Weight: 8 Pounds
MSRP: $1,190
URL: www.mossberg.com
THE VERDICT
With its detachable magazine, the 590 RM provides more firepower without adding barrel/magazine tube length. It is available with a cylinder choke using Accu-Choke choke tubes or a cylinder bore with a standoff device for breaching. This would make an excellent combination for law enforcement.
That’s all for now, folks! Please keep sending in your questions, tips, and article ideas. And as always – “Let’s Be Careful Out There.”
Friedrich Seiltgen is a retired Master Police Officer with 20 years of service with the Orlando Police Department. His writing has appeared in RECOIL, Soldier of Fortune, The Counter Terrorist Magazine, Off Grid, American Thinker, Homeland Security Today, and The Journal of Counterterrorism & Homeland Security International.
Contact him at [email protected].