I’ve been waiting for this announcement since October of 2022 when I first got the chance to shoot Mossberg’s new shotgun, the 990 AfterShock.

I’ve been waiting – impatiently – because this is such a fun gun to shoot, runs like the proverbial bat out of hell, and is a great ‘get out of my house’ option. I already own one of Mossberg’s 590S Shockwaves, but after shooting the semi-auto AfterShock I quickly decided I wanted, and needed, a 990.

Mossberg’s semi-auto gas system has evolved from the pre-930 options, to the 930, then the 940 to what is offered today. The current gas system’s functionality and reliability is the result of further development by Mossberg’s engineers for an over-seas defense contract, which required the system to do more in a shorter space.

What you get in the new 990 AfterShock is a gas system that cycles fast and reliably in the short system of a pistol-grip shotgun with a 14.75” barrel and an overall length of only 27.125”.

The reliability of the system is enhanced by the corrosion-resistant internal parts and their finishing. The gas piston, magazine tube, hammer and sear are nickel boron-coated. The gun also features an enlarged/beveled loading port, elongated elevator, and anodized follower combining for a smooth operation.

In other words, you can feed the AfterShock as fast as you can get those mechanics down, and empty it even faster.

Naturally the AfterShock is outfitted with extended controls – a knurled charging handle and an oversized, ergonomic paddle-style bolt release – just as the 940 Tactical and the 940 Pro models are, which makes operation so much more pleasant. At this point it’s hard to figure out why any shotgun maker would not incorporate these competition-proven features into a semi-auto, especially the tactical variants.

For such a small shotgun, Mossberg packed a number of features into the design. Photos courtesy of Mossberg

Short shotguns of this type are not overly easy to handle, though many think they are until they eat a fist full of pistol grip because they underestimated how firmly they need to push the shotgun forward as they fire it. Thankfully, this is usually a self-correcting mistake that is only made once.

The 990 AfterShock is designed to mitigate some of this with a forend strap that safely keeps the lead hand clear of the muzzle allowing you better control when firing. The grip features a rubberized palm pad for shooting comfort, and is uniquely shaped to provide a firm grip and to minimize felt recoil.

The ergonomics are there and those, coupled with how the semi-auto’s gas system eats recoil, the 990 AfterShock is surprisingly comfortable to shoot – and very manageable.

Feature-wise the last notable aspects are a rear swivel stud port and a magazine tube extension fixture with multi-sided M-LOK®-compatible slots for quick and easy accessory customization.

Mossberg is releasing three 6-shot models of the AfterShock. The AfterShock (#83001) is the main model in the launch. The AfterShock model for states that hate short guns (#83002) comes with 18.5” barrel giving it an overall length of 30.875”. Finally there is the AfterChock equipped with a CrimsonTrace Lasersaddle (#83003).

While I didn’t run one of the models sporting the Crimson Trace Lasersaddle at the Gunsite media day, several others did. The design is aesthetically solid and the utility of a laser-equipped tactical/home defense shotgun is undeniable, just like the appeal of going with this particular model. Photo courtesy of Mossberg

Out on the Gunsite Range

The features and specs, along with the photos, are enough to sell a lot of people on buying an AfterShock but it’s out on the range where you realize you’d like to add one of these to your gun safe.

Mossberg’s media day was, again, held at Gunsite Academy. If you haven’t been to Gunsite to take a class, you really should look into it. For companies looking to host a media event in the Western U.S., Gunsite is hands-down one of, if not the best location for such an event.

Mossberg brought plenty of the new but as yet unreleased 990 AfterShocks to the range, both with and without the Crimson Trace Lasersaddle. Photo: P. Erhardt

As I said, the 990 is a great shooting gun. Running drills out on the range is the perfect way to familiarize yourself with the new shotgun, even if my hits weren’t ideally positioned at center mass on the target. But that’s exactly why these kinds of events are so helpful in understanding a new product.

A little low and to the right but with all nine pellets on target it’s a shot nobody is walking away from anytime soon. Photo: P. Erhardt

Each shooter handled the 990’s recoil a bit differently based on their experience and strength. The difference between shooting the 990 versus the 590S Shockwave, a pump-action, is significant because the gases in the 990 are redirected to cycle the next round, thus absorbing recoil in a different way.

Using a strong grip on the 990 while holding the forend firmly, within the strap, and pushing forward keeps the shotgun in position for followup shots. Loosen your grip, or let the shotgun ride up and directly back at you and your recovery to the appropriate sight picture takes valuable time.

Once you get a feel for how the shotgun handles when firing it’s just a matter of adjusting your front and rear gripping pressure. Which, of course, is exactly why you need to take the 990 for a test drive to get to know it. Knowing how it patterns with your selected ammo is also really important. Photo: P. Erhardt

There’s one last feature to point out. You may have noticed from the images taken during the Gunsite media event that the original models we test fired were outfitted with a traditional bead front sight. The new models being announced today all come with a fiber-optic front sight. For me, fiber-optic front sights are the only way to go and I’m glad they made this particular upgrade.

If you plan on attending the NRA Show in Atlanta this weekend you will want to be sure to swing by the Mossberg booth #2837 to check out the new 990 AfterShock. If a short tactical/self defense shotgun is on your wish list, this is where you’ll find it.

And if you already own one of the excellent Mossberg 940 Tactical models, you might as well pick up its little brother, the 990 AfterShock.

— Paul Erhardt, Managing Editor, the Outdoor Wire Digital Network