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Rainier Arms RUC MOD 4 5.56 NATO Piston Rifle - 16" Black

AR-15 Rifle


We are excited to introduce to you our new RUC MOD 4 with the  Superlative Arms short stroke adjustable piston system. When we first introduced our RUC Series of rifles, our focus was to develop a weapon that integrated a lightweight design while using the highest quality components. Building on the solid foundation of its predecessors, our new RUC MOD 4 is a light weight, high quality and high performance rifle that is heavy on value. It features our new Rainier Arms 15” Urban Combat Rail, FHV2 Flash Hider, and RA Mod 2 Ambidextrous Safety Selector Switch. We have also included Kriss USA Steel backup iron sights for the RUC Mod 4!

Upper Parts:

  • Rainier Arms Chrome-Moly Vanadium 5.56mm 16" Nitride Barrel
  • 1 in 7" twist
  • Extended M4 Feed Ramps
  • MPI/HP tested Bolt
  • 1/2x28 threads
  • Mid length gas system
  • Superlative Arms .750 Adjustable Piston System
  • Rainier Arms Avalanche MOD2 Charging Handle
  • RA Forged A4 upper receiver
  • RA Night Rail 15" fix
  • Rainier Arms Flash Hider - FHV2
  • Steel Flip-Up Front & Rear Sights - Kriss USA

Lower Parts:

  • RA Forged Lower
  • Mil-Spec 6 position receiver extension
  • H2 Buffer
  • B5 Systems Bravo Stock
  • Magpul MOE+ K2 Grip
  • ALG QMS trigger
  • Rainier Arms Selector Switch Mod 2- Standard 90 Degree/ Short (50 Degree).
  • BCM QD end plate

Additional info:

  • One 30 rd Magpul PMAG Gen 2 magazine where legal
  • Case Included
  • Weight 7 lbs 3.2 oz
More Information
Product Type AR-15 Rifle
Manufacturer Rainier Arms, LLC
Gas Block Diameter .750"
Thread Pitch 1/2x28
Gas Length Mid
Barrel Length 16"
Caliber 5.56 NATO
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