Strike Industries Aluminum Extended Magazine Plate for SIG SAUER P320 9mm SI EMP AL P320 SI EMP AL P320 BK UPC 793811766578
Product Description
The Strike Industries® Aluminum Extended Magazine Plate for SIG SAUER P320 (9mm) (SKU: SI-EMP-AL-P320 / UPC: 793811766578) elevates your secondary weapon capacity by delivering +5 additional rounds of 9x19mm Parabellum in a rugged, competition-ready footprint. Purpose-built for competitive USPSA shooters, tactical operators, and home-defense specialists, this extended basepad replaces the factory polymer floorplate with a solid billet aluminum reservoir that maximizes magazine payload without introducing unnecessary bulk or snag hazards.
Precision CNC-machined from aerospace-grade 6061-T6 billet aluminum, this extended basepad provides exceptional impact resistance during aggressive speed reloads on concrete, gravel, and packed dirt. The exterior surface is treated with an abrasion-resistant MIL-A-8625 hardcoat anodize that resists surface gouging, aggressive bore solvents, and environmental perspiration. Unlike flexible polymer extensions that can crack under extreme duty drops, the rigid 6061-T6 housing maintains structural squareness to eliminate feed-lip distortion and internal follower binding under full 20+ round spring compression.
Engineered to comply with USPSA 140mm race division gauge restrictions, the Strike EMP optimizes overall length for maximum capacity within sanctioned match parameters. Ergonomic relief cuts along the flank profile provide positive thumb and finger purchase to manually rip stubborn or fouled magazines from the receiver during failure-to-extract diagnostics. Secured by a slide-on retention track and dual M4 locking set screws, the assembly eliminates floorplate slide-off under cyclic recoil while maintaining simple armorer-level field stripping for spring maintenance.
*Armorer Bench Notes & Real-World Staging Guidance:*
Fitment Matrix: Direct slide-on fitment for factory OEM SIG SAUER P320 steel 15-round, 17-round, and 21-round 9mm magazines across full-size, carry, and compact grip modules. CRITICAL: Not compatible with 10-round factory compliant/dimpled magazines or aftermarket magazines (ACT-MAG, ProMag, ETS). When installing on 21-round tubes, you MUST use the included SI extra-power spring; 15-round and 17-round tubes require re-use of the factory SIG OEM spring. Do NOT exceed 7 in-lbs (0.79 N·m) of torque on the M4 set screws. Allow an initial break-in period for 21-round tubes, as stamped steel tolerances may yield +4 capacity on first loading before achieving +5.
- Ensure the host firearm is completely clear, magazine removed, slide locked open, and the chamber physically and visually confirmed empty before bench assembly.
- Depress the factory magazine floorplate detent insert with an armorer punch, slide the factory polymer baseplate forward off the steel magazine rails, and carefully capture the compressed magazine spring and follower.
- Select the correct spring configuration: swap to the included Strike Industries extra-power spring for 21-round magazine bodies, or retain the factory SIG OEM spring for 15-round and 17-round magazine bodies.
- Compress the spring and follower fully inside the magazine tube, align the Strike Aluminum EMP with the steel floorplate rails, and slide the extension fully rearward until seated flush against the magazine stop lip.
- Using the included 2mm hex wrench, tighten the dual M4x3mm set screws evenly until they contact the magazine retaining surface, ensuring torque does NOT exceed 7 in-lbs (0.79 N·m), then hand-cycle dummy rounds to verify follower travel and slide lockback.
Key Features
- Plus-Five Round 9mm Capacity: Expands magazine capacity by +5 rounds across factory SIG P320 15, 17, and 21-round steel magazine bodies.
- CNC-Machined 6061-T6 Billet Aluminum: Structural aerospace-grade housing shrugs off hard impacts during high-speed competition reloads on abrasive surfaces.
- MIL-A-8625 Hardcoat Anodized Finish: Durable tactical matte black surface treatment resists chemical solvents, holster wear, and corrosion.
- USPSA 140mm Division Compliant: Engineered to fit inside official USPSA 140mm race division measurement gauges for sanctioned match readiness.
- Low-Drag Anti-Snag Profile: Contoured exterior lines prevent snagging on duty gear, plate carriers, and concealment apparel during rapid draws.
- Dual M4 Set Screw Retention: Secures the basepad to the magazine rails without movement; torques down securely using the provided 2mm hex tool.
- Dedicated Extra-Power Spring Included: Ships with an engineered high-tensile spring specifically tuned for proper feeding and lockback on 21-round magazine tubes.
Product Specifications
- Brand: Strike Industries®
- Model/Series: Aluminum Extended Magazine Plate for SIG SAUER P320 (9mm)
- MPN / SKU: SI-EMP-AL-P320 / SI-EMP-AL-P320-BK
- UPC: 793811766578
- Material: CNC-Machined 6061-T6 Billet Aluminum
- Finish: MIL-A-8625 Hardcoat Anodized (SI Blackline)
- Fastener Spec: Dual M4x3mm Steel Set Screws (Max 7 in-lbs / 0.79 N·m)
- Capacity Increase: +5 Rounds (9x19mm Parabellum)
- Length: 1.37 Inches (34.80 mm)
- Width: 1.10 Inches (27.94 mm)
- Height: 1.39 Inches (35.31 mm)
- Competition Class: Fits USPSA 140mm Race Division Gauge
- Platform Compatibility: OEM SIG SAUER P320 9mm Magazines (15-Rd, 17-Rd, 21-Rd)
- Country of Origin: Taiwan
