Quick Answer: What is the PMAG Gen3 +5 Pre-Installed Magazine Extension?
The Shield Arms PMAG Gen3 +5 Pre-Installed Magazine Extension is a factory-assembled 35-round magazine combining a genuine Magpul PMAG Gen3 30-round magazine with our precision-machined +5 aluminum extension. This pre-installed solution eliminates the guesswork of installation and delivers immediate, reliable performance for your AR-15 platform rifle.
What you get:
- Complete ready-to-use 35-round magazine (PMAG + extension pre-installed)
- Works with factory PMAG spring - no modifications required
- Easy-access floor plate for maintenance without disassembly
- Also available: PMAG Gen3 Window version for visual round count
Maximize Your AR-15 Capacity with Pre-Installed Reliability
The PMAG Gen3 +5 Pre-Installed Magazine Extension delivers 35 rounds of trusted capacity in a single, ready-to-use package. By combining Magpul's proven PMAG Gen3 platform with Shield Arms' precision-machined aluminum extension, this magazine eliminates installation concerns while providing the extended capacity you need for competition shooting, training, or defensive applications. Each magazine arrives fully assembled, tested, and ready for immediate deployment.
Engineered specifically for the AR-15 platform, this extended magazine maintains the reliability and feeding characteristics that have made the Magpul PMAG the industry standard. The Shield Arms +5 extension is machined from billet 6061 aluminum and features a Type 2 anodized finish for exceptional durability. Unlike competitor extensions that require disassembly for maintenance, our innovative easy-access floor plate allows you to service the spring and follower without removing the extension from the magazine body—saving time and preventing potential reassembly issues.
Whether you're running drills at the range, competing in 3-gun competitions, or building a home defense setup, the additional 5-round capacity provides a meaningful tactical advantage without compromising the proven PMAG reliability. The extension adds minimal length while maximizing magazine capacity, and the integrated index cuts provide enhanced grip when drawing from magazine pouches or plate carriers. Backed by our 100% lifetime warranty and "Spring for Life" guarantee, this is the last magazine extension you'll need to buy.
Key Features
- 35-Round Total Capacity: Genuine Magpul PMAG Gen3 30-round magazine with pre-installed +5 extension
- Easy-Access Floor Plate: Revolutionary design allows spring and follower maintenance without removing extension from magazine body
- Billet Aluminum Construction: CNC-machined from solid 6061 aluminum for exceptional strength-to-weight ratio
- Type 2 Anodized Finish: Military-grade hard anodizing provides superior corrosion and wear resistance
- Index Grip Cuts: Machined texturing on extension body improves grip during magazine changes and pouch draws
- Factory Spring Compatible: Engineered to work flawlessly with the original PMAG spring—no aftermarket springs required
- Pre-Installed & Tested: Factory-assembled and function-tested before shipping for immediate reliability
- Made in USA: Proudly manufactured in the United States with premium American materials
Why Choose Pre-Installed?
While magazine extensions can be installed by the end-user, our pre-installed option offers several distinct advantages. First, it eliminates any installation errors that could affect feeding reliability. Second, it saves you valuable time—these magazines are ready to load and shoot immediately upon arrival. Third, it ensures optimal assembly tension and alignment, which our experienced technicians verify during the manufacturing process. For shooters who value convenience and guaranteed performance, the pre-installed option is the smart choice.
Technical Specifications
| Specification |
Details |
| Total Capacity |
35 rounds (30rd PMAG + 5rd extension) |
| Compatible Firearms |
AR-15 platform rifles (5.56 NATO / .223 Remington) |
| Magazine Base |
Magpul PMAG Gen M3 (Generation 3) |
| Extension Material |
6061-T6 Billet Aluminum |
| Finish |
Type 2 Hard Anodized (Black) |
| Spring |
Factory Magpul PMAG spring (included) |
| Weight |
Approximately 5.2 oz (empty) |
| Overall Length |
Standard PMAG length + 1.25" extension |
| Country of Origin |
Made in USA |
| Warranty |
100% Lifetime Warranty + "Spring for Life" Guarantee |
PMAG Gen3 Standard vs. Window Configuration
| Feature |
Standard PMAG Gen3 +5 |
Window PMAG Gen3 +5 |
| Capacity |
35 rounds |
35 rounds |
| Visual Round Count |
No window |
Viewing windows on magazine body |
| Weight |
Slightly lighter |
Minimal weight difference |
| Durability |
Maximum impact resistance |
Excellent durability with window design |
| Price |
Same price |
Same price |
Frequently Asked Questions
Is this compatible with my AR-15?
Yes, this magazine is compatible with all standard AR-15 platform rifles chambered in 5.56 NATO or .223 Remington. It works with mil-spec magazine wells and most aftermarket magazine well designs. The PMAG Gen3 has been tested across hundreds of rifle configurations and is widely considered the most reliable polymer magazine available.
Do I need to buy a special spring for the +5 extension?
No, the Shield Arms +5 extension is specifically engineered to work with the factory Magpul PMAG spring that comes installed in the magazine. This design eliminates the need for aftermarket springs and ensures optimal reliability.
How do I clean and maintain this magazine?
The innovative easy-access floor plate allows you to service the magazine spring and follower without removing the extension from the magazine body. Simply press the floor plate release, slide the plate open, and you can access the internal components for cleaning or inspection. This design makes maintenance significantly faster than traditional extensions that require complete disassembly.
What's the difference between the standard and window versions?
Both versions offer identical 35-round capacity and use the same Shield Arms +5 extension. The only difference is that the window version features Magpul's PMAG with viewing windows on the magazine body, allowing you to visually confirm your remaining round count. Both versions are priced identically, so the choice comes down to personal preference—the window version is popular with competition shooters, while the standard version is preferred by those prioritizing maximum durability.
Are extended capacity magazines legal in my state?
Magazine capacity restrictions vary by state and locality. Currently, several states have restrictions on magazines holding more than 10 or 15 rounds. It is the buyer's responsibility to verify that this 35-round magazine is legal in their jurisdiction before purchasing. Shield Arms cannot ship restricted items to prohibited locations and assumes no liability for the buyer's compliance with local laws.
Will this fit in my standard magazine pouches?
The +5 extension adds approximately 1.25 inches to the overall length of the standard PMAG. Most magazine pouches designed for AR-15 magazines will accommodate this extended length, though some low-profile competition pouches may be tight. The index grip cuts on the extension body actually improve purchase when drawing from deeper pouches or plate carrier setups.
What does the lifetime warranty cover?
Shield Arms provides a 100% lifetime warranty covering defects in materials and workmanship for as long as you own the product.
Can I install additional extensions on this magazine?
No, this magazine comes with the +5 extension already installed and should not be modified with additional extensions. The magazine and extension are designed as an integrated system, and adding further extensions could compromise reliability and safety. If you need even greater capacity, we recommend purchasing additional complete magazines.
How does this compare to drum magazines?
While drum magazines offer higher capacity (typically 50-100 rounds), the PMAG Gen3 +5 provides a better balance of capacity, reliability, and practicality for most users. At 35 rounds, this magazine gives you a significant capacity increase over standard 30-round magazines without the added bulk, weight, and complexity of drums. It's also more reliable—PMAG-based magazines have fewer moving parts and are less prone to feeding issues than drum designs.
Is the aluminum extension durable enough for hard use?
Absolutely. The extension is CNC-machined from billet 6061-T6 aluminum, the same aerospace-grade alloy used in aircraft components and high-end rifle parts. The Type 2 hard anodizing process creates an exceptionally hard, corrosion-resistant surface that stands up to impacts, drops, and rough handling. Many tactical and competitive shooters trust aluminum magazine extensions in demanding environments where reliability is non-negotiable.
How quickly will this ship?
Pre-installed magazines typically ship within 1-3 business days of order placement. Because these magazines are assembled and tested before shipping, there may be slightly longer lead times during periods of high demand compared to individual components. You'll receive tracking information via email as soon as your order ships.
Who Should Buy This Magazine?
- Competition Shooters: 3-gun competitors, USPSA rifle division shooters, and anyone running timed courses who needs reliable extended capacity
- Firearms Instructors: Training professionals who need extended capacity for demonstrations and high-volume shooting days
- Home Defense Users: Responsible gun owners who want increased capacity for defensive applications
- Range Enthusiasts: Recreational shooters who want to spend more time shooting and less time reloading
- AR-15 Owners: Anyone looking to maximize their rifle's capabilities with proven, reliable components
- Convenience Seekers: Shooters who prefer the reliability of pre-installed, factory-tested magazines over DIY installation
- Quality-Focused Buyers: Those who demand American-made products backed by comprehensive warranties
Made in USA with Pride
Every Shield Arms product is designed, engineered, and manufactured in the United States using premium domestic materials. Our commitment to American manufacturing ensures superior quality control, supports domestic jobs, and allows us to maintain the highest standards throughout the production process. When you choose Shield Arms, you're investing in American craftsmanship and supporting the domestic firearms industry.
Related Products & Accessories
- PMAG Gen3 Window +5 Pre-Installed Magazine Extension - Prefer visual round count verification? This window version offers the same reliability and capacity with the added benefit of viewing windows for quick ammunition checks during competition or training.
- Additional Magazines: Consider building a complete magazine loadout—most competitive shooters and serious users maintain at least 6-10 magazines for training and match use.
- Magazine Storage Solutions: Protect your investment with proper magazine storage pouches or cases designed for extended-length AR magazines.
Warranty & Support
Shield Arms stands behind every product with our 100% lifetime warranty covering defects in materials and workmanship. For installation guidance, maintenance tips, and product support, visit our installation and support resources.
Order Your PMAG Gen3 +5 Pre-Installed Magazine Extension Today
Upgrade your AR-15 with proven reliability and extended 35-round capacity. Every magazine ships fully assembled, tested, and ready for immediate use. Experience the Shield Arms difference—precision engineering, American manufacturing, and lifetime support.
