Geissele Automatics Super Duty MOD1 5.56 NATO Complete AR-15 Upper Receiver - 13.9" Pinned - DDC - 08-546S
Only 1 left in stock
Elevate your AR-15 build with the Geissele Automatics Super Duty MOD1 5.56 NATO Complete Upper Receiver – a pinnacle of precision engineering designed for tactical enthusiasts and competitive shooters who demand unrelenting reliability and performance. This 13.9-inch pinned upper in Desert Dirt Color (DDC) delivers combat-proven components in a ready-to-install package, ensuring seamless integration and superior accuracy right out of the box.
Key Features
- Premium Barrel Construction: Features a 13.9-inch cold hammer-forged (CHF) barrel with chrome lining and a 1:7 twist rate, optimized for stabilizing a wide range of 5.56 NATO ammunition while maintaining a medium profile for balanced handling and heat dissipation.
- Advanced Rail System: Equipped with a 13.5-inch MK16 Super Modular Rail (SMR) featuring Geissele’s innovative center tab for rock-solid accessory mounting, allowing quick and secure attachment of optics, lights, and grips without compromising barrel harmonics.
- Reliability-Enhanced BCG: Includes Geissele’s Nanoweapon®-coated bolt carrier group with a Stressproof® bolt and asymmetric cam pin, reducing friction and wear for smoother operation and extended service life in demanding conditions.
- Optimized Gas System: Mid-length gas system with a super compact gas block and precisely tuned .076-inch port size to minimize recoil and ensure consistent cycling, even under suppressed fire.
- High-Quality Muzzle Device: Factory-installed HUXWRX Flash Hider (QD 556) with Nanoweapon® coating for reduced flash signature and quick suppressor attachment, enhancing low-light performance and versatility.
- Ergonomic Charging Handle: Airborne Charging Handle (ACH®) for ambidextrous operation, making reloads faster and more intuitive during high-stress scenarios.
Technical Specifications
- Caliber: 5.56 NATO
- Barrel Length: 13.9 inches (pinned and welded for 16-inch legal compliance)
- Barrel Finish: Manganese phosphate
- Barrel Profile: Geissele tapered medium contour
- Twist Rate: 1:7 RH
- Gas System: Mid-length
- Receiver Material: Forged 7075-T6 aluminum with Super Duty enhancements
- Overall Length: Approximately 23.25 inches
- Weight: 67 ounces
- Color: Desert Dirt Color (DDC) for tactical camouflage
- Includes: Complete BCG, charging handle, and all necessary hardware
Why Choose the Super Duty MOD1 Upper?
This upper addresses common AR-15 pain points like inconsistent reliability and suboptimal ergonomics by incorporating Geissele’s battle-tested innovations. The pinned 13.9-inch configuration offers the maneuverability of a shorter barrel without legal hurdles, ideal for home defense or close-quarters training. Its robust construction withstands extreme abuse, while the tuned gas system reduces felt recoil by up to 20% compared to standard setups, allowing faster follow-up shots. Whether you’re customizing a duty rifle or enhancing a personal build, this upper provides unmatched durability and precision, backed by Geissele’s reputation for excellence in firearms components.
Ready to upgrade your AR-15 with professional-grade performance? Secure the Geissele Super Duty MOD1 upper today and experience the difference in accuracy, reliability, and control that top-tier engineering delivers.
Frequently Asked Questions
Q: Is this upper compatible with standard AR-15 lowers?
A: Yes, it mates perfectly with mil-spec AR-15 lower receivers, ensuring drop-in compatibility for most builds.
Q: What does ‘pinned’ mean for the barrel?
A: The muzzle device is pinned and welded to extend the effective barrel length to 16 inches, complying with federal regulations while preserving the compact 13.9-inch profile.
Q: Can I use a suppressor with this upper?
A: Absolutely – the included HUXWRX flash hider features quick-detach threads, making it suppressor-ready for enhanced versatility.
| Weight | 67 oz |
|---|---|
| Dimensions | 23.25 × 3.5 × 3.5 in |
| Barrel Finish | Mag Phosphate |
| Barrel Profile | Medium |
| Cartridge Compatibility | 5.56 NATO |
| Barrel Length | 13.9 |
| Gas System Length | Midlength |
| Twist Rate | 1-7 |
| BCG / Charging Handle | Included |
| MPN | 08-546S |
| UPC | 810081133999 |
Compliance
NFA (National Firearms Act) compliance is crucial for legal ownership and transfer of regulated firearms and accessories like short-barreled rifles, suppressors, and certain types of ammunition, ensuring adherence to federal regulations to avoid legal penalties and ensure responsible firearm ownership.
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