Mossberg’s 12-Gauge Model 590
Shockwave Smoothbore “Firearm.”
; .

The compact Mossberg 590 Shockwave is designed to be
fired from the waist position only!

Mossberg enters 2017 with a new corporate slogan, “Arm Yourself,” and with the selection of arms spread across the pages of their 2017 catalog, the job of arming yourself has never been easier. Without exaggeration, Mossberg dominates the world of tactical model shotguns.

New in the line this year is a real head-turner, the Model 590 “Shockwave,” a 6-shot, 12-gauge, pump-action firearm sporting a short 14-inch barrel and a pistol grip you can purchase right over the counter without a National Firearms Act (NFA) application or transfer tax.

We’re conditioned to believe a conventionally stocked shotgun must have an 18-inch barrel to avoid being classified as a “Short Barreled Shotgun” requiring NFA paperwork and a $200 transfer tax. Ah, but there are subtleties within subtleties when it comes to the federal classification of firearms.

For example, did you know Mossberg offers two, sub-compact, 12-gauge firearms with 7.5-inch and 10.25-inch barrels, pistol grips and fold-down foregrips you can legally purchase? Known as the Models 590A1 and 500 Compact Cruisers, these exotic numbers are federally classified as “Any Other Weapon” (AOW), not “Short Barreled Shotguns,” because they have pistol grips—not conventional stocks—and an overall length of less than 26 inches (can be concealed). But you are required to fill out NFA paperwork with an NFA dealer and pay a $5 transfer tax to buy them.

Which brings us to the classification of the 2017 “Shockwave.” Take a factory new Model 590 receiver never originally stocked. Add a Raptor pistol grip and now it’s classified as “Pistol Grip Only” (PGO) because it’s a shotgun not designed to be fired from the shoulder. Add a 14-inch barrel, bringing the overall length to over 26 inches (not easily concealed) and the total package is now classified as a “Non-NFA Firearm” requiring only a Form 4473 to purchase. Simple, eh? Unfortunately, some states and jurisdictions have laws prohibiting its sale or ownership.

The new Shockwave is the result of a collaboration between Mossberg and Shockwave Technologies. Shockwave designed both the signature bird’s head “Raptor” grip and the strapped fore-end to prevent your hand from slipping forward over the muzzle of the 14-inch barrel while pumping the action. Both parts can be purchased directly from Shockwave Technologies and their web page even explains the procedures the owner of an existing Pistol Grip Only Model 500 Mossberg with its 18.5-inch barrel (it must have left Mossberg as a Pistol Grip Only 500) can follow to convert their PGO into a Raptor-gripped, 14-inch barreled, Non-NFA Firearm. If your Model 500 ever had a buttstock fitted, you can’t convert it to a Shockwave.


Mossberg has long offered pistol-gripped tactical smoothbores like
this Model 500 (top). The 14-inchbarreled Shockwave (below) is still
longer than 26 inches overall.

In use, the long, textured Raptor grip’s contoured bird’s head design minimizes felt recoil in the palm of the hand and provides maximum control of this 26.37-inch-long firearm while use of the strapped fore-end is essential unless you want to gamble on losing a digit or two or losing hold of the firearm during recoil. Mossberg has added a sling swivel to the butt of the Raptor grip for a 2-point sling carry. Better yet, I would use a short, shotgun scabbard like the Voodoo if I really, really had to carry it for any distance.

Mossberg designed the Shockwave to be fired at waist level only. The owner’s manual specifically states “Upon firing, recoil force will cause the firearm to move rearward and upward. Never hold the firearm at eye level and attempt to sight down the barrel.” The Shockwave barrel does sport a brass bead front sight, but it’s there to be picked up only in your peripheral vision for better alignment of the short barrel with the target.

For the familiarization phase, I shot up a box of Winchester’s AA Extra-Lite Target loads featuring 1 ounce of No. 7.5 shot. Recoil was moderate, and after 25 rounds, my muscle memory was pretty well calibrated so I could place effective patterns from a high waist position on a B-27 silhouette target at ranges from 7 to 30 feet.

What would improve the Shockwave’s effectiveness and accuracy would be a fore-end, like Mossberg’s Tri-Rail, fitted with laser and light units.

To gauge the Shockwave’s 5+1 defensive qualities, I focused on three, different, 2-3/4-inch shotshells: Super-X buffered 00 buck; S&B No. 4 buck and Winchester’s hybrid PDX loading (1-ounce slug + three 00 buck). Since there seems to be quite a bit of interest in them, I also included Exotic Products’ 1-3/4-inch mini-type shell, stack-loaded with 00 buck and 7.5 shot. All final test targets were shot at 10 yards (30 feet).

Firing the buckshot loads moved the needle way up in terms of felt recoil. I found pushing my forward hand tightly up against the strap of the fore-end and maintaining a very firm grip on the fore-end helped immensely in controlling felt recoil and muzzle flip.

The patterns delivered by the 14-inch cylinder bore, heavy-walled barrel of the Shockwave were well centered and well distributed. Any one of the four different loads fired would have taken the fight out of an adversary. Frankly, I was impressed how well the Shockwave fulfilled its defensive niche.

In terms of load performance, the Winchester PDX shell centering a 1-ounce slug surrounded by three 00 buck would simply be devastating. However, the pattern is only 4-inches in diameter—great for an aimed shot but a little too tight to be relied upon when shot from the hip. The 00 buck pattern surprised me by holding 12 pellets in a tight 5-inch diameter pattern. I have the greatest respect for 33-caliber 00 buck but 5-inch patterns delivered from the waist are perhaps a bit too tight. The 21 pellet No. 4 buck load would be my first choice spreading its 24-caliber pellets out into an 8-inch pattern.


Winchester’s PDX slug/buck combo load is devastating but the pattern is too tight at 30 feet.

The .33-caliber 00 buck load has long been a favorite in the 12 gauge,
but its pattern is still tight at 30 feet.

Holt’s defensive choice would be 4 Buck with its 21 pellets covering 8 inches at 30 feet.

Exotic Products’ 00 Buck/7.5 shot mini-combo shell delivered excellent patterns at 30 feet.

Exotic Products 1-3/4-inch mini-type shells are often mentioned as a good 8+1 loading in the Shockwave. I was surprised at the excellent quality of 12-inch patterns delivered by Exotic Products’ “Jungle Juice” shell consisting of three 00 buck and a dollop of 7.5 shot plus the reduced recoil of the little shell was a welcome relief. Would I recommend mini-shells for serious purposes? No! They will not feed properly in the Shockwave without the installation of the rubber OPSol Mini-Clip guide in the magazine loading port and in testing the OPSol Mini-Clip, I’ve found it is not thoroughly reliable. In fact, the maker of the Mini-Clip recommends its use for “recreational shooting” purposes only.

The Shockwave is not a “car gun.” It is too long, too heavy, too unwieldy and requires two hands to operate—better a 1-hand, handgun with 17 rounds of firepower.

For home defense, I would rather have a conventionally stocked Model 590. It’s easier to control, to aim, holds 9-rounds of standard 2-3/4-inch ammunition and with a Mossberg Tri-Rail fore-end, could be fitted with a laser and a light. The Shockwave may be an ideal, under-the-counter firearm for shopkeepers. Time will tell.

Wading a brushy stream in Alaska with grizzlies around? You bet. Loaded with slugs and slung across my back in a short shotgun scabbard, it would be mighty comforting.

Predator calling with my back against a rock or tree, I would appreciate having the Shockwave at my side if black bears or mountain lions couldn’t resist my odd notes.

In the meantime, Mossberg’s exotic-looking Shockwave is a unique and ground-breaking addition to their extensive line of tactical firearms. My final thought is the Shockwave may be a cool-looking firearm, but it’s not a gun to be purchased, fired a few times and then set aside. It’s a waist-level-held-thumper you must initially master and then requires you to maintain your proficiency with thorough periodic practice. It’s a darn demanding firearm.


MAKER: O.F. Mossberg & Sons
7 Grasso Ave.
North Haven, CT 06473
(800) 383-3555

ACTION: Pump-action
GAUGE: 12, CHAMBER: 3-inch
CAPACITY: 4+1 (3-inch), 5+1 (2-3/4-inch), 8+1 (1-3/4-inch)
BARREL LENGTH: 14 inches
OVERALL LENGTH: 26.37 inches
CHOKE: Cylinder bore
WEIGHT: 5.3 pounds
FINISH: Matte blue
STOCK: Shockwave Technologies Raptor grip and strapped fore-end
SIGHTS: Front brass bead
PRICE: $455

Subscribe To American Handgunner