MPN: STU5435-R3S


  • Caliber: 5.56 NATO
  • Finish: Type III Class 2 Hardcoat Anodized Finish
  • Upper Receiver: Spike's Tactical Forged M4 Flat Top Upper - Made from 7075-T6 aluminum
  • Handguard: Spike's Tactical Lightweight 13.2" BAR2 Quad-Rail - Made from 6061-T6 aluminum
  • M4 Feed Ramps: Yes
  • Muzzle Device: Mil-Spec A2 Flash Hider
  • Barrel: 16” 1:7 Twist Optimum profile 5.56 NATO CHF Barrel
  • Muzzle Thread Pattern: 1/2"-28
  • Gas Block: Spike's Tactical .750" Micro Gas Block (A2 front sight gas block for 9" rail)
  • Gas Tube: Mid-Length Melonited Gas Tube
  • Bolt Carrier Group: Spike's Tactical Mil-Spec M16 Bolt Carrier Group
  • Charging Handle: Mil-Spec Charging Handle


  • Weight: ~4 lbs. 2 oz.


  • AR-15 lower receiver


  • 1x Spike's Tactical ST-15 Upper 16" Mid-Length 5.56 CHF Barrel w/ BAR2 Rail
  • 3x Rail covers
  • 1x QD swivel


It’s time for a new AR-15 and this time you want to build it yourself with the best parts you can afford, but where are you going to start? If you’re looking for a high-value component package with an outstanding barrel, have a look at this Spike's Tactical ST-15 Upper with 16" Mid-Length 5.56 CHF Barrel and BAR2 Rail System.

The barrel included in this Spikes Tactical mid-length upper assembly is a beautiful Cold Hammer Forged 5.56 barrel that was created with the specifications of the NATO M249 SAW in mind. CHF barrels are work hardened by hammer forging the blanks while they are held on solid mandrels that also impress the lands and grooves into the bore. Following SAW specs the chamber and bore of these barrels are plated with Hard Chrome almost twice as thick as the Mil-Spec chrome in other 5.56 barrels. Each barrel is High-Pressure Tested and Magnetic Particle Inspected and given a Mil-Spec Black Phosphate finish. The result is an extra durable barrel with rifling that you can expect to remain in service for upwards of 20,000 rounds.

The Spikes upper receiver included in this mid-length upper assembly is the Spike’s ST-15. The ST-15 was created with the needs of law enforcement tactical groups in mind. The ST-15 is precision machined from a 7075-T6 Aluminum blank for lightweight strength that you can count on. Features like extended feed ramps and Dryfilm lubricant interior coating ensure reliable operation every time your rifle cycles.

Last but not least, Spikes includes their BAR2 Rail system in this package. This rail certainly isn’t an afterthought, it’s a unibody quad rail that’s designed oversized so it’s a better fit for bigger hands and allows a little extra space for gas blocks and suppressor cans. The rails feature scalloping that not only looks hot but eliminates the cheese grater effect that so many forends can have when used without rail covers. Since it’s made of 6061-T6 Aluminum and given an anodized hard coat, you can count on this hand guard in the field without worrying if it’s tough enough to handle the job.

As a whole, you can see that this Spikes Tactical ST-15 Upper 16" Mid-Length 5.56 CHF Barrel with BAR2 Rail complete upper assembly is an excellent value. It’s not likely that you’ll find a receiver, barrel and hand guard of this quality anywhere else that represents the value you get in this bundle. Save yourself the time and trouble. Choose a Spikes upper assembly. Get off the bench and back to the range.

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