Stern Defense 004Sdbu45D1M 45 Acp Mag Phosphate 8620 Steel Ar15/M16

The Stern Defense 004Sdbu45D1M is a 45 ACP magazine purpose-built for AR15 and M16 platforms configured to chamber that cartridge. If you've got an AR-pattern rifle or carbine in 45 ACP—whether you built it yourself or picked up a dedicated upper—you need reliable magazines that feed without drama. This one combines proven materials with straightforward design: an 8620 steel body finished in phosphate coating that resists corrosion and wear.

Phosphate finish on steel magazines is industry standard for good reason. It bonds to the metal at a molecular level, creating a durable barrier against rust and surface damage. That matters when you're running practice drills, hunting, or storing gear in less-than-ideal conditions. The 8620 steel keeps the magazine rigid and dimensionally stable through thousands of rounds, so feed lips stay in spec and your gun runs reliably.

AR-15 and M16 pattern 45 ACP builds have become more common as shooters seek softer-shooting, easier-to-suppress alternatives to 5.56 NATO. If that's your platform, having magazines engineered for that specific combination beats improvising with incompatible hardware. Stern Defense built this one for that job.

Key Features

• 8620 steel construction for durability and consistent dimensions
• Phosphate finish resists corrosion and surface wear
• Designed specifically for 45 ACP chambered in AR15/M16 platforms
• Straightforward, proven design for reliable feeding

Specifications

Frequently Asked Questions

Will this magazine work in my 45 ACP AR-15?

Yes. The Stern Defense 004Sdbu45D1M is specifically engineered for AR15 and M16 platforms chambered in 45 ACP. It's designed around that cartridge and firearm combination.

What's the advantage of 8620 steel with phosphate finish?

8620 steel is tough and maintains its shape through repeated use. Phosphate coating bonds directly to the steel and creates a corrosion-resistant surface that holds up under field conditions and storage without requiring constant maintenance.

Can I use this in a standard 5.56 NATO AR-15?

No. This magazine is chambered for 45 ACP and built to function in AR-15/M16 platforms set up for that caliber. Using it in a rifle of a different caliber will not work reliably and is unsafe.