Mossberg 590 Shockwave 12 Gauge – 14.375-Inch Barrel – 50659
The Mossberg 590 Shockwave 12 Gauge, model 50659, combines the established Mossberg 590 pump-action platform with the distinctive Shockwave Raptor bird's-head grip and a compact 14.375-inch heavy-walled barrel. Measuring 26.37 inches overall and weighing approximately 5.25 pounds, the factory configuration differs from both conventional shoulder-stocked shotguns and traditional handguns.
Introduced in 2017, the original 590 Shockwave brought Mossberg's well-established pump-action operating system into a specialized configuration without a shoulder stock. The firearm incorporates the familiar Mossberg 590 design features, including dual extractors, twin action bars, positive steel-to-steel lockup, and an anti-jam elevator.
Distinctive Raptor Bird's-Head Grip
The Shockwave Technologies Raptor grip is one of the defining characteristics of this model. Its curved bird's-head profile distinguishes the Shockwave from conventional pistol-grip firearms and contributes to the factory configuration's overall dimensions.
A black synthetic corncob-style forend incorporates a retention strap. The strap provides an additional hand-positioning reference while the pump-action mechanism is operated.
Original Mossberg 590 Operating System
The 590 Shockwave retains the mechanical features associated with Mossberg's pump-action design: dual extractors, twin action bars, steel-to-steel lockup, and an anti-jam elevator. An ambidextrous top-mounted safety provides a familiar control layout for users accustomed to Mossberg 500 and 590 platforms.
The heavy-walled 14.375-inch barrel features a matte-blue finish, cylinder-bore choke and front bead sight. The receiver is drilled and tapped for compatible accessories, subject to the manufacturer's requirements.
12-Gauge Chamber and Capacity
Model 50659 is chambered for 12-gauge shotshells up to 3 inches in length and has a factory capacity of five rounds in the magazine plus one in the chamber when using the manufacturer's specified standard ammunition.
This is the original 590 Shockwave rather than the later 590S model. The 590S has a redesigned feeding system for additional shell-length flexibility; those 590S-specific capabilities should not be assumed for model 50659.
Federal Classification and FFL Transfer
In its original factory configuration, Mossberg identifies the 590 Shockwave as a non-NFA firearm under federal law. Although commonly grouped with shotguns in retail catalogs, the factory model is classified as a Gun Control Act firearm rather than a conventional shoulder-fired shotgun.
FFL transfer required. Purchaser must be at least 21 years of age. State and local restrictions may apply. See Extended Information for additional classification and compliance details.
California Proposition 65 Warning: This product can expose users to chemicals including lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, visit www.P65Warnings.ca.gov.
Related Products & Accessories
Explore related Mossberg-compatible equipment and shooting accessories available through Huckleberry Arms. Always confirm specific firearm and ammunition compatibility before use.
- 12-Gauge Shotgun Shells: Browse available shotgun ammunition and review individual load specifications. Model 50659 has a 3-inch chamber; confirm appropriate shotshell length, type, and manufacturer recommendations.
- Shotguns & Pump-Action Firearms: Compare other available sporting and security-oriented firearms with different barrel lengths, capacities, stocks, and operating systems.
- Target Cameras: Explore remote target-observation equipment for reviewing shooting results at established ranges.
Mossberg 590 Shockwave – Classification, Compatibility & Buyer Information
Is the Mossberg 590 Shockwave a Shotgun or a Pistol?
The original Mossberg 590 Shockwave, model 50659, has a distinctive federal classification. Although it fires conventional 12-gauge shotshells and uses the Mossberg 590 pump-action mechanism, the factory firearm is not classified as an ordinary shoulder-fired shotgun or a pistol under the Gun Control Act.
The Shockwave was originally manufactured without a shoulder stock and has a factory overall length of 26.37 inches. Mossberg identifies this configuration as a non-NFA firearm under federal law.
For federal dealer-transfer purposes, the original factory configuration is generally recorded as an Other Firearm on ATF Form 4473. It is not transferred as an ordinary long gun merely because it uses shotshell ammunition.
Does the Mossberg 590 Shockwave Require a Tax Stamp?
In its original factory configuration, no. Mossberg's model 50659 is classified as a non-NFA firearm and does not require an NFA tax stamp or NFA registration for an ordinary lawful dealer transfer.
This classification is independent of the October 9, 2026, ATF nationwide nonenforcement policy concerning certain NFA-regulated firearms.
October 9, 2026 – ATF National Firearms Act Guidance
On October 9, 2026, the Bureau of Alcohol, Tobacco, Firearms and Explosives announced that it would exercise nationwide enforcement discretion regarding NFA making, transfer, approval, and registration requirements for covered short-barreled rifles, short-barreled shotguns, silencers, and firearms classified as Any Other Weapons (AOWs).
The policy follows the federal district court decision in Silencer Shop Foundation v. ATF. It does not repeal the NFA, and the underlying statutory provisions remain in effect. The policy may be revised or withdrawn.
Applicable Gun Control Act provisions, FFL transfer requirements, background checks, and state and local restrictions remain applicable. Separate federal transport requirements may apply to firearms classified as short-barreled shotguns.
For current federal guidance, see ATF – Update to NFA Transfer Guidance.
Can a Shoulder Stock Be Installed on a 590 Shockwave?
Changing the original Shockwave configuration may change its federal firearm classification. Installing a shoulder stock on a firearm with a barrel shorter than 18 inches may result in a configuration classified as a short-barreled shotgun under federal law.
ATF's October 9, 2026, guidance provides nationwide nonenforcement of specified NFA provisions for covered firearms, but does not eliminate the underlying statutory definitions or supersede state and local restrictions.
Owners should evaluate any proposed configuration changes under current federal guidance and applicable state and local law before modifying the firearm.
Does Changing the Grip Affect Classification?
Overall length and whether a firearm is designed to be fired from the shoulder are among the factors relevant to federal classification. Shortening the factory Shockwave configuration below the applicable overall-length threshold can raise additional classification questions, including whether the resulting firearm falls within the NFA definition of an Any Other Weapon.
The October 2026 nonenforcement policy covers specified AOW classifications but does not resolve every possible configuration or state-law restriction. Do not assume that all modifications to the Shockwave are legally equivalent to its original factory configuration.
What Ammunition Does Model 50659 Accept?
The original Mossberg 590 Shockwave 50659 is chambered for 12-gauge shotshells with a maximum shell length of 3 inches. Its factory magazine capacity is five rounds, with an additional round accommodated in the chamber.
This model should not be confused with the later Mossberg 590S Shockwave. The 590S incorporates a redesigned feeding system specifically intended to accommodate 1.75-inch, 2.75-inch, and 3-inch shotshells in various combinations.
Do not assume that the original 590 Shockwave 50659 will reliably cycle short mini-shell ammunition without a manufacturer-approved solution. Always follow Mossberg's ammunition guidance.
Can the Barrel Use Interchangeable Chokes?
Model 50659 has a factory cylinder-bore barrel rather than an interchangeable choke-tube system. The barrel is not listed by Mossberg as Accu-Choke compatible.
Does the Shockwave Need an FFL Transfer?
Yes. The original Mossberg 590 Shockwave is a firearm subject to federal Gun Control Act requirements. Huckleberry Arms ships firearms only to eligible Federal Firearms Licensees for lawful transfer.
Minimum Federal Dealer-Transfer Age: 21 Years. Additional state or local eligibility requirements may apply.
Customers must provide an eligible receiving FFL and ensure the selected firearm is lawful for possession and transfer in their jurisdiction. Huckleberry Arms does not ship complete firearms to California.
Is the Mossberg 590 Shockwave Legal in Every State?
No. Although Mossberg's factory configuration is a non-NFA firearm under federal law, individual states and local jurisdictions may use different definitions or impose additional restrictions. Federal classification does not guarantee lawful possession or transfer everywhere.
Huckleberry Arms reviews applicable shipping restrictions before fulfillment. Customers and receiving dealers are responsible for confirming compliance with the laws governing the intended transfer and possession.
California Proposition 65 Warning
WARNING: Use of this product can expose you to chemicals including lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, visit www.P65Warnings.ca.gov.