Rosco K9 Saucepack Barrel Kit – 5.56 NATO, 12.5” Patrol Length, Nitride, Includes BCG, Gas Tube & Non-Adjustable Gas Block, AR-15 Compatible

The Rosco K9 “Saucepack” is a high-performance, mission-ready barrel kit made for professionals and serious builders who demand reliability in a compact setup. With a 12.5” patrol-length gas system, nitride finish, and included BCG, gas tube, and gas block, this kit is plug-and-play for any short-barreled AR-15 upper build.

Unlock reliable performance with the Rosco Manufacturing K9 “Saucepack” — a complete 12.5” 5.56 NATO barrel kit designed for law enforcement, duty use, and high-end AR builders. This barrel system is engineered around Rosco’s patrol-length gas system, delivering smoother cycling and optimal reliability in suppressed or unsuppressed setups.

Constructed from 4150 CMV steel with a black nitride finish, the 12.5” K9 barrel is tough, corrosion-resistant, and built to last. The Saucepack includes a matching bolt carrier group, non-adjustable gas block, and patrol-length gas tube, giving you all the key components to upgrade or complete your upper with premium parts.

⚙️ Key Features:

• Caliber: 5.56 NATO / .223 Remington

• Barrel Length: 12.5″

• Gas System: Patrol Length – Smoother recoil impulse, ideal for SBR setups

• Barrel Material: 4150 CMV Steel

• Barrel Finish: Salt Bath Nitride – Corrosion & heat resistant

• Twist Rate: 1:7 – Stabilizes heavier 62–77gr projectiles

• Muzzle Thread: 1/2×28 – Suppressor and muzzle device ready

• Includes:

  • Rosco K9 12.5” Barrel

  • Mil-spec Bolt Carrier Group

  • Patrol-Length Gas Tube

  • Low-profile, non-adjustable gas block

• Platform: AR-15

• Made in the USA

Whether you’re building out a short-barreled rifle (SBR) or a pistol upper, the Rosco K9 Saucepack gives you the critical components trusted by professionals — no guesswork, just top-tier reliability.

FAQ:

Q: What is a patrol-length gas system?
A: It’s longer than a carbine but shorter than mid-length, designed by Rosco for smoother cycling and reduced wear, especially in suppressed or high-volume use.

Q: Does this kit include everything for a complete upper?
A: This is a barrel kit — it includes the barrel, BCG, gas tube, and gas block, but you’ll need a receiver, handguard, and muzzle device to complete your upper.

Q: Can I use this barrel with a suppressor?
A: Yes — the 1/2×28 threading and patrol-length gas system make it suppressor-friendly and tuned for reliable performance.

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