Agency Arms +5 Magazine Extension for SIG Sauer P320 Black - BP-320-BLK

Agency Arms +5 Magazine Extension - Fits Sig Sauer P320 Magazines, Anodized Black Finish - SKU: BP-320-BLK - UPC: 810012470005

Product Description

The Agency Arms +5 Magazine Extension for SIG Sauer P320 (BP-320-BLK) is a premium, hard-use extended base pad engineered to expand ammo capacity, improve grip leverage, and facilitate rapid magazine stripped reloads across SIG P320 handguns. Designed to increase standard 9mm magazine capacity by 5 rounds (or .40 S&W capacity by 4 rounds), this extension is an essential upgrade for tactical operators, competition shooters, and defensive staging.

Precision CNC-machined from 6061-T6 aircraft-grade billet aluminum and finished in a Mil-Spec Type III hardcoat black anodizing, the BP-320-BLK features a set-screw retaining pin design that locks the extension body securely onto the factory magazine floorplate rails. Aggressive relief cuts and side grip serrations provide positive tactile purchase when stripping stuck magazines during clearing drills or fast reload transitions.

The Agency Arms P320 magazine extension comes complete with an extra-power extended chrome silicon magazine spring to ensure uniform, high-velocity round elevation and 100% slide lock-back capability on the final shot.

*Armorer Bench Notes & Real-World Staging Guidance:
Fitment Matrix: Fits factory OEM SIG Sauer P320 9mm/.40 S&W full-size and compact steel magazines. (Compatible with standard P320 grip modules, Agency Arms magwells, and X-Series grip modules).

1. Verify host firearm is completely clear, magazine removed, and chamber visually and physically confirmed empty.
2. Depress the factory magazine insert floorplate pin and slide the original plastic baseplate off the magazine body.
3. Remove factory spring and insert while retaining the OEM follower.
4. Install the included Agency Arms extended spring onto the OEM follower and compress into the steel magazine body.
5. Slide the Agency Arms BP-320-BLK base pad onto the magazine bottom rails and tighten the top set-screw snugly into the indexing notch to lock it in place.

Key Features

• +5 Round Capacity Expansion: Adds 5 extra rounds of 9mm Luger (or 4 rounds of .40 S&W) to standard OEM SIG P320 steel magazines.
• 6061-T6 Billet Aluminum Body: Machined from high-strength aluminum to survive high-impact drop falls onto concrete range bays.
• Type III Hardcoat Black Anodized: Premium matte finish provides supreme scratch resistance and corrosion protection.
• Secure Set-Screw Retention Lock: Integrated locking set-screw prevents accidental base pad detachment under high dynamic impact.
• Tactical Strip Grooves: Machined side cuts allow positive leverage to manually rip stuck magazines clear of the magwell.
• Extended Spring Included: Ships complete with a high-tensile chrome silicon drive spring to guarantee reliable feeding.

Product Specifications

• Brand: Agency Arms
• MPN: BP-320-BLK
• SKU: BP-320-BLK
• UPC: 810012470005
• Platform Compatibility: SIG Sauer P320 OEM Magazines (9mm / .40 S&W)
• Capacity Increase: +5 Rounds (9mm) / +4 Rounds (.40 S&W)
• Material: 6061-T6 Billet Aluminum
• Finish/Color: Matte Black Hardcoat Anodized
• Included Accessories: Extended Base Pad, Set Screw, Extra Power Spring