• Adjustable length of pull (LOP) from 12.25" to 16.5" - 28 Possible locking Positions
  • Aluminum pistol grip/stock adapter
  • Adapter accepts standard AR-15 grips and buffer tubes
  • Comes with AB Arms Urban Sniper Stock and Ergo pistol grip


  • Weight: 1 lb 7.4 oz. (Complete system)
  • Material:
    • Adapter: 6061-T6 aluminum
    • Stock: Polymer
    • Pistol Grip: Polymer with over molded rubber
  • Length (when installed):
    • Min: 9.75"
    • Max: 14"
  • Finish: Black


  • Mossberg 500


  • 1x AB Arms Urban Sniper Stock
  • 1x Ergo pistol grip
  • 1x Stock/pistol grip adapter
  • 1x Adapter screw
  • 1x Pistol grip screw


Why should rifles get all the glory? The shotgun is a tactical weapon in its own right. The weapon needs to fit the needs of the warrior, and sometimes the job requires the special skill set of a shotgun. There aren’t a lot of stellar options on the market for upgrade Mossberg 500 stocks, but AB Arms really brings something to the table with their MOD-X M500 Tactical Mossberg 500 Pistol Grip and Stock System.

Easy Upgrade, Solid Construction

The MOD-X is a Mossberg 500 stock replacement that is designed to be a direct “drop-in” replacement for the Mossberg’s factory stock. The MOD-X M500 bolts on with the help of an adapter machined from 6061-T6 aluminum. It’s light, so it’s not a major encumbrance, but the superior quality, aircraft grade aluminum isn’t about to leave you in the lurch. A sleek, hard anodized coating ensures that the adapter blends in perfectly with all of your black tactical equipment and won’t draw attention to itself.

Fixed Stock with a Flexible Length of Pull

The MOD-X M500 Mossberg Stock System features AB Arms’ Urban Sniper Stock and an Ergo pistol grip. While the stock is fixed, it features a spring-loaded butt pad, and the length of pull can be adjusted from 12.25 to 16.5 inches and anywhere in between. You can really customize the fit with an astounding 28 different locking positions. The Ergo Pistol Grip gives you the confident feel of your favorite short barreled rifle while offering added value in the form of a battery compartment that accepts both AA and CR123 cells so you can carry extra juice for your favorite accessories.

Yes, You Can Upgrade Further

If you’re not happy using the Ergo Grip as your Mossberg 500 pistol grip, the adapter will easily accept your favorite AR grips. If you’re wanting to change things up later, the MOD-X’s AB adapter will accept any carbine length receiver extension.

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