The STT-15 Big Bore PILLAR Upper Receiver Combo is incredibly light coming in at 8.2oz! It features an enlarged ejection port to freely pass .458 SOCOM all the way up to .50 BEOWULF. We designed the STT-15 Big Bore PILLAR upper receiver to overcome the shortcomings we saw in the current offerings. 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 STT-15 Big Bore PILLAR Billet Receiver Combo will accommodate a variety of big bore calibers and attaches to an STT-15 lower or any AR15 lower you currently have.
The STT-15 Lower receiver was designed out of necessity and a desire to have a true ambidextrous AR-15 \ M4 platform. Allowing it to accommodate any and all shooters without the need to add countless costly add-ons. Whether you are a right or left-handed shooter or forced to shoot with your off-hand, the STT-15 has you covered! STT-15 is designed specifically for situations in which there's no room for error and you must use your rifle to take that shot!
Machined directly from a billet of 7075-T651 aerospace grade American aluminum on our brand new Haas CNC machinery. This allows us to hold ultra-tight tolerances and make sure that the final product is exactly as designed. The finished receiver is then finished in Mil-Spec, MIL-A-8625 Type III hard anodizing.
CERAKOTE orders are sprayed to order and require a two week lead time.
BLANK (No Logo Engraving) options will take up to 6-8 weeks to be available for shipping
- Action - Semi-Auto
- Weight – 8.2 Ounces
- Dimensions - Length: 7.69” Width: 1.490” Height: 4.015”
- Material - Billet 7075-T651 Aerospace Grade Aluminum
- Finish - Matte Black MIL-A-8625 Type III Hard Anodize
- Component Compatibility - Works With All Mil-Spec AR-15\M16 Components And Lower Parts Kits.