Mossberg 590 Shockwave 12 Gauge Pump-Action, 14.375 in Barrel, 3 in Chamber, Cyl Bore, Side Saddle, Matte Black
This Mossberg 590 Shockwave is a compact 12 gauge with a 14.375 in cylinder-bore barrel, a 3 in chamber, and a matte black finish. It has been customized with a receiver-mounted six-round Side Saddle that integrates a Picatinny top rail, plus a barrel/magazine clamp with a short accessory rail near the muzzle. The gun is marked with the standard 590 receiver designation (not 590A1), and the bore condition is excellent.
Key functional features include a front bead sight, ambidextrous tang-mounted safety, and a black synthetic bird's-head grip with a ribbed polymer fore-end. Magazine capacity is 4+1 with 3 in shells. This setup delivers a practical configuration with on-gun ammunition storage and mounting options while keeping the Shockwave's compact profile.
3" Chamber. Cyl Bore. Side Saddle.
Condition
Overall Condition: Good condition, showing some signs of prior use and handling.
Bore Condition: Excellent - Clean, mirror finish, no signs of wear.
Specific Condition Notes: There are markings consistent with prior handling and use. The fore-end strap appears to have been removed by a previous owner.
What’s Included
- Receiver-mounted six-round side-saddle shell holder (installed)
- Receiver Picatinny top rail (installed; integrated with the shell carrier)
- Barrel/magazine clamp with short Picatinny accessory rail near the muzzle (installed)
The Shockwave configuration centers on a 14.375 in cylinder-bore barrel and a compact overall profile. The single front bead sight provides a straightforward aiming reference, and the ambidextrous tang safety is easy to access from either hand.
This example is set up with practical upgrades. The receiver-mounted six-round shell carrier keeps spare 12 gauge shells on the gun, and its integrated Picatinny top rail provides a solid mounting surface. A barrel/magazine clamp near the muzzle adds a short accessory rail for a light or other compact accessory.
The chamber accepts both 2 3/4 in and 3 in shells, with a magazine capacity of 4+1 when using 3 in shells. The cylinder bore is well-suited to general-purpose defensive loads. The bore itself is bright and clean.
Controls and furniture are classic 590 Shockwave: a black synthetic bird's-head grip, a ribbed polymer fore-end, and an ambidextrous tang safety. The receiver is marked as a standard 590 (not 590A1), and the overall matte black finish rounds out the package.
Made in the United States, this customized Shockwave brings together compact dimensions, a Cyl Bore barrel, a 3" Chamber, and an on-board Side Saddle for efficient shell management.