Strike Alum Ext Mg Plt P320 9Mm Fde

The Strike Industries Aluminum Extended Magazine Plate for SIG SAUER P320 9mm is a precision-engineered accessory designed to maximize your magazine capacity without sacrificing reliability or competitive compliance. Machined from 6061-T6 aluminum, this extended mag plate bolts onto OEM SIG P320 magazines to add five rounds of usable capacity—a meaningful upgrade for range sessions, training, and USPSA competition where every round counts. It's lightweight at just 1.97 ounces and engineered with a slim, low-drag profile that won't snag on gear or holsters.

Installation is straightforward: the included extended spring (sized for 21-round magazine bodies), set screws, hex tool, and instructions make setup quick and tool-light. The design is intentionally minimal—no unnecessary bulk, no gimmicks—which is why it remains one of the slimmest extended plates available and meets USPSA 140mm race division limits. Strike offers the plate in anodized SI BLACKLINE or FDELINE (Flat Dark Earth) finishes, so you can match your gun's aesthetic without compromise.

Compatibility is broad but specific: the plate works with OEM SIG SAUER P320 magazines in 21-round, 17-round, and 15-round configurations across most SIG grip modules. The included spring is optimized for 21-round bodies and delivers the full +5 capacity after a break-in period; 17- and 15-round magazines use the factory spring and may achieve +4 capacity initially. It's not designed for 10-round magazines, aftermarket brands like ACT or ETS, or some aftermarket magwells. Keep torque on the set screws under 7 inch-pounds to avoid over-tightening.

Whether you're prepping for a match, running drills at the range, or simply want more rounds before a reload, the Strike P320 extended mag plate delivers proven function without weight penalty or bulk.

Key Features

• Adds five rounds of 9mm capacity to OEM SIG P320 magazines
• Machined 6061-T6 aluminum construction for durability and lightweight performance
• Works with 21-round, 17-round, and 15-round OEM SIG magazine bodies
• Slim, low-drag profile—minimal snag and no excess bulk
• Meets USPSA 140mm race division limits for competitive shooting
• Simple installation with included spring, set screws, and hex tool
• Available in SI BLACKLINE or FDELINE anodized finishes
• Just 1.97 ounces—negligible weight addition

Specifications

Frequently Asked Questions

Will this fit my SIG P320 magazines?

Yes, if you're using OEM SIG SAUER P320 magazines in 21-round, 17-round, or 15-round sizes and most SIG grip modules. The included extended spring is designed for 21-round magazine bodies and provides the full +5 capacity after break-in. The 17-round and 15-round magazines use the factory OEM spring and may initially achieve +4 capacity. The plate does not fit 10-round magazines, and compatibility with some aftermarket magwells is not guaranteed. Aftermarket magazines from ACT, ProMag, or ETS are not supported.

What comes in the box?

You get the aluminum extended mag plate, one extended spring sized for 21-round magazines, two M4x3mm set screws, a 2mm hex tool for installation, and a warning card with important setup information.

Is this legal for competition?

Yes. The Strike P320 extended mag plate meets USPSA 140mm race division limits, making it a solid choice for competitors running PCC or pistol divisions. Always verify your specific match rules before competition.

How much does it weigh?

The plate weighs only 1.97 ounces, so it adds virtually no bulk or weight to your magazine and gun setup—important if you're running drills or competition where every ounce matters.