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San Tan Tactical STT-15 PILLAR Billet Upper Receiver

AR-10 Stripped Upper Receiver



Let’s be honest…. There are a trillion different ar-15 upper receivers on the market today. When we were designing this one there were short comings with the current offerings that needed to be addressed. It needed to be lighter, stronger, and different, and all while looking good doing it. We weren’t going to settle for just hacking another receiver out of a block and calling it good.

The first thing people will notice is the truss pockets. With the shooting styles of today’s shooters everyone wants to run 15" & 16" long rails and grip the rail as far out as possible to gain the most control of the rifle. That’s like attaching a 16" lever to the rifle. The truss design acts similar to a bridge that carries and distributes the stress across the entire platform verses putting all of the stress on the material right behind the threads of the receiver. The extra strength gained from this design is not only to help the receiver. It also in turn helps improve your accuracy.

When most people think of a billet receiver they think of a blocky, heavy, thick design that is CNC machined. We wanted to break that mold too. Thru the use of 3D CAD modeling software we were able to save weight in places that extra material didn’t have a purpose, such as the forward assist block and the shell deflector. Normally on billet uppers those are left bulky due to the difficulty of removing material on all of those angles. After all of was said and done the new STT receiver came in at only 8.2 ounces. That’s lighter than some slick side uppers!

Overall we strived to offer the shooter something that wasn’t just another pretty face in the crowd. We wanted an upper that would really address the issues of today shooters.


  • San Tan Tactical Truss pockets for increased structural rigidity.
  • Cut from a single billet 7075 -T651 aerospace grade aluminum.
  • Shell deflector
  • Fully Assembled with forward assist, and ejection port cover.
  • Machined in T markings for easy optic relocation.
  • Machined with M4 feed ramps.
  • Machined to mil-spec standards.
  • Interfaces with all AR15/M16/M4 weapons systems and accessories.
  • Mil Spec Type III class II hard coat anodized Black
  • No roll pin design. (Forward assist attaches via threaded dowel pin)
  • Lightweight- Weighs in at only 8.9 Ounces. Who said billet had to be heavy!
  • Compatible with a multitude of rail manufacturers anti rotation tabs.
  • Compatible with all known battery assist lever on the market today.
  • Backed by STT’s unmatched lifetime warranty.
  • Made in the USA!
More Information
Product Type AR-10 Stripped Upper Receiver
Option AR-15

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