Geissele Automatics Super Duty MOD 1 SD-556 — 16" 5.56 NATO Semi-automatic Rifle (Excellent)
Purpose-built for hard use yet refined enough for the discerning collector, this Super Duty MOD 1 pairs Geissele’s aerospace-grade machining with battlefield-proven ergonomics. A cold-hammer-forged, chrome-lined 16" barrel, full-ambidextrous controls, and the SSA-E X two-stage trigger come together in a rifle that feels as smooth on the bench as it is confident on the clock. If you have been hunting for a factory-built AR-15 that needs no upgrades out of the box, this is the one.
Condition
• Overall: Excellent — only the faintest handling evidence, no finish loss on high edges.
• Bore: Mirror-bright with razor-sharp lands and grooves.
• Internal components: Nanoweapon-coated bolt carrier group shows no wear patterns; Super 42 buffer spring is clean and untarnished.
What’s Included
• 1 × 30-round Magpul PMAG GEN M3 magazine
• Geissele factory cardboard rifle box with matching part number/serial label
Geissele’s reputation was forged in the world of precision triggers, and that pedigree is obvious the moment you touch the flat-faced Lightning Bow. The 3.5 lb SSA-E X breaks like glass for precise shots yet offers a reassuring second stage for dynamic work. Recoil impulse is noticeably softened by the proprietary, extra-long “Geissele-length” gas system and the Super 42 braided spring, while the HUXWRX Flash Hider-QD’s Nanoweapon finish laughs off heat, carbon, and even saltwater.
The 15" MK16 handguard—with anti-rotation center tab and stainless QD inserts—gives you maximum sight radius and M-LOK real estate without sacrificing rigidity. Whether you are mounting IR lasers, a barricade stop, or a night-vision bridge, the rail stays locked in place. The Stressproof alloy bolt is HPT/MPI inspected, and every major component is final-machined in-house to aerospace tolerances, ensuring parts fit together with a vault-like absence of rattle.
Fully ambidextrous controls—including the Super Configurable Safety levers, Airborne Charging Handle, and checkered paddle mag release—make the rifle equally intuitive for left- and right-handed shooters. Suppressor users will appreciate the out-of-the-box HUXWRX QD interface and the pinned Super Compact Gas Block that won’t walk under heat.
With an MSRP of $2,035, the Super Duty MOD 1 already represents one of the best turnkey performance rifles available. Finding a gently used example in this condition—and with every original component intact—simply shortens the path between you and your next range session.
Own a rifle engineered for a lifetime of reliability, tuned by the people who set the standard for combat-grade AR parts, and delivered in condition that lets you be the one to put the first honest wear on it.