Last year, Mossberg introduced the 990 AfterShock, a semi-automatic Shockwave-type “firearm" with a brand-new action design. New for 2026, the company is expanding their 990 series with the 990 SPX Magpul shotgun and the 990 SPX AfterShock.
Features introduced with the original 12-gauge, 3-inch-chambered 990 include a gas-operating system, knurled charging handle, oversize safety and bolt release and an enlarged and beveled loading port with an anodized follower. Both the new 990 shotgun and AfterShock versions are given Mossberg’s “Special Purpose Tactical” (SPX) treatment. This includes an optic-ready receiver using the Shield RMSc footprint. The shotgun includes three adapter plates that allow for the mounting of optics with a RMR, Docter and Leupold DPP footprint. The SPX models also have a re-designed fore-end that has an integrated heat shield, M-Lok accessory slots, and QD sling swivel ports.
The 990 SPX Aftershock will come in two versions, both of which have a fiber-optic front sight. The first is in the Shockwave configuration with a 14.75-inch barrel and five-round capacity. This will be available in three finish options: matte black ($1,204), OD Green or Flat Dark Earth Cerakote finishes ($1,260 each). It will also be offered in a standard shotgun configuration, with an 18.5-inch barrel and an AfterShock pistol grip, with a matte black finish. This version has an MSRP of $1,204.
The 990 SPX Magpul uses an SGA stock with a spacer system for adjusting length of pull and built-in sling swivel ports. In addition to its optics-ready receiver, it is drilled and tapped for additional optic mounting options and comes with metal ghost ring sights. It will also be offered in two versions, both with a matte black finish. The first has an 18.5-inch barrel and a seven-round capacity. The second has a 14.75-inch barrel and a five-round capacity, and falls under the provisions of the National Firearms Act. While short-barreled shotguns (SBS) still require registration, there is no longer a $200 tax stamp required for their purchase.
For more information, see the company’s 990 SPX Magpul and 990 AfterShock websites.
