Geissele Automatics 5.56 NATO 13.9" Barrel - Mid-Length Gas - Maganese Phosphate Finish

Geissele Automatics 5.56 NATO 13.9" Barrel - Mid-Length Gas - Maganese Phosphate Finish

Engineered for maximum endurance, unyielding reliability, and match-grade consistency, the Geissele Automatics 13.9" 5.56 NATO Cold Hammer Forged (CHF) Barrel represents the ultimate foundation for a hard-use carbine or custom pin-and-weld rifle build. Precision-machined and cold-hammer-forged in North Wales, PA, from high-grade Chrome Moly Vanadium steel, this barrel is designed to endure extreme firing schedules while maintaining exceptional accuracy. Its versatile 13.9-inch length offers an ideal balance of compact maneuverability and full ballistic efficiency, allowing shooters to achieve a 16-inch legal rifle length when pinned and welded with an appropriate muzzle device.

Featuring Geissele's proprietary Taper Profile, this barrel intelligently distributes weight to enhance barrel stiffness and thermal stability without adding unnecessary front-end bulk. The interior bore is lined with heavy-duty chrome for superior corrosion resistance and extended throat life, while the exterior is protected by a tough manganese phosphate finish. Tuned with a mid-length gas system and a precise .081 gas port for smooth, reliable cycling with or without a suppressor, every barrel is High Pressure Tested (HPT) and Magnetic Particle Inspected (MPI) to guarantee flawless structural integrity.

Features

Cold Hammer Forged (CHF) Construction:
Forged under immense pressure from Chrome Moly Vanadium steel to create a dense, highly durable molecular structure capable of handling extreme heat and rapid firing schedules.

Heavy-Duty Chrome Lined Bore & Chamber:
Provides maximum corrosion resistance, reduces friction, and significantly extends barrel life under continuous high-volume use.

Geissele Taper Profile:
Optimized profile distribution maximizes barrel rigidity and heat dissipation where it matters most, reducing POI shift while preserving lightweight front-end handling.

Mid-Length Gas System Architecture:
Delivers a smoother recoil impulse, reduced bolt carrier velocity, and lowered internal component wear compared to traditional carbine-length gas systems.

Ideal 13.9" Length for Pin & Weld Builds:
Provides a compact form factor that achieves a legal 16" non-NFA rifle length when pinned and welded with select extended muzzle devices.

HPT and MPI Inspected:
High Pressure Tested (HPT) and Magnetic Particle Inspected (MPI) to identify microscopic flaws and ensure total reliability under pressure.

Precision M4 Feed Ramps:
Includes factory-cut M4 feed ramps to ensure reliable, smooth cartridge feeding from the magazine into the chamber.

Manganese Phosphate Outer Finish:
Heavy phosphate coating shields the outer steel surface against abrasion, harsh moisture, and chemical exposure in demanding field environments.

Specifications