L&S Ls9mm55-36 5.5 Ar9 Nitride Brl 1/2X36

The Lead & Steel LS9MM55-36 is a 5.5-inch AR9 barrel built for shooters who want a compact, maneuverable setup without sacrificing velocity or reliability. Engineered for 9mm AR platforms, this nitride-finished barrel delivers the durability and corrosion resistance that serious shooters demand—whether you're running a home-defense build, a short-stroke competition rig, or an SBR project where every inch of length matters. The nitride treatment stands up to frequent shooting and harsh conditions, so you're getting a barrel that performs and lasts.

At 5.5 inches, you're trading some velocity compared to full-length barrels, but you gain the handling and portability that make tight spaces manageable. Pair it with a compatible AR9 bolt and lower receiver, and you've got a proven platform. The 1/2x36 threading means you can run suppressors, flash hiders, or muzzle brakes designed to that spec—giving you control over your finished setup.

Lead & Steel focuses on no-nonsense components that work, and this barrel reflects that philosophy. If you're building or upgrading an AR9 pistol or short-barreled rifle, this nitride 5.5-inch barrel is a straightforward, reliable choice that won't let you down on the range or in the field.

Key Features

• 5.5-inch length optimized for compact AR9 builds
• Nitride finish resists corrosion and extends service life
• 1/2x36 threading accommodates standard suppressors and muzzle devices
• Designed for 9mm AR platform compatibility

Specifications

Frequently Asked Questions

What AR9 receivers and bolts work with this barrel?

This is a standard 9mm AR barrel designed for AR9 platform builds. Confirm your lower receiver and bolt carrier group are also chambered in 9mm and compatible with AR9 systems before assembly.

Can I use a suppressor or muzzle brake with the 1/2x36 threading?

Yes. The 1/2x36 thread pitch is the standard for AR9 muzzle devices. Any suppressor or flash hider threaded to 1/2x36 will fit this barrel.

Is this barrel suitable for SBR or pistol builds?

Yes. The 5.5-inch length is purpose-built for compact AR9 pistol and short-barreled rifle configurations where maneuverability and shorter overall length are priorities.

What does the nitride finish do?

Nitride treatment hardens the barrel surface and provides corrosion resistance, extending the life of the barrel and reducing maintenance needs under regular use and variable conditions.