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Quarter Circle 10 Blu Whistler (Sig Sauer P320) Side Charging Receiver Set

Lower Receiver

Special Price $396.99 Regular Price $529.99

The QC10 receiver set represents the bare essentials for a quality pistol/carbine build. The stripped lower and upper with proprietary parts form a solid foundation from which to completely customize a pistol or carbine. Some customers purchase this kit as an upgrade to their existing platforms, while others try their hand at matching the performance of a QC10 full build with other components. Regardless, the QC10 Receiver kit ensures the heart of the build is American. Made for, not modified, with a connection to Texas that no one else can match.


  • QC10 Stripped P320 Lower Receiver with proprietary parts
  • Accepts mil-spec receiver extension (buffer tube)
  • QC10 Side Charging Upper Receiver with Gibbz Arms Technology 
  • Latching, Non-Reciprocating Charging Handle
  • Engineered for 9mm Sig P320 Magazines
  • Accepts QC10 Universal 9MM Bolt Assembly
  • Type III Hard Coat Anodizing
  • No Lower Parts Kit installed
  • Made For the AR Platform- Not Modified
  • Handguards with overlapping anti-rotation tabs may not be compatible with QC10 billet upper receivers, including Side Charging uppers.
  • **GIBBZ Arms Patented Left Side Charging Handle Pat. No. 9,310,146
More Information
Product Type Lower Receiver
Manufacturer Quarter Circle 10
Color Black
Caliber 9mm

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