Shipping: All orders are shipped within 72 hours Monday -Thursday 6am - 4pm Arizona Time.
Any order containing a lower receiver will not be shipped until we receive a copy of your FFL. Once received regular shipping policies apply. Submit your FFL Here.
Holiday Shipping: The QC10 Shop is closed from December 223rd-January 2nd. During this time, shipping will also be closed. You order will be processed on Jauary 2nd and will ship out the same or next week. Please double check your shipping information as well as get your FFL info in so that your order will not be delayed.
Returns: Quarter Circle 10 offers a 30 day return, refund and exchange policy. See Details.
The outstanding feature of the QC5 is that it is made for the use of 9x19mm MP5 magazines. Available in a full range of hand guard and barrel lengths in either a rear or side charging receiver. Users appreciate that in a QC10 complete build, all components are made for, not modified to work together. This dependability is further strengthened by a life time warranty and dependable customer service.
Engineered for 9x19mm MP5 magazines
Mil-Spec Lower parts
Milled billet 7075-T6 Aluminum Lower Receiver
QC10 Milled billet 7075-T6 Aluminum Rear Charging Upper Receiver
Type III Hard Coat Anodizing
Made For The AR Platform- Not Modified
Choice of barrel lengths & matching MLOK handguard
Endless customization options
Test fired before it leaves the factory
Includes Carrying Case
Quarter Circle parts are designed to work within mil-spec perimeters. However, for optimum performance we recommend using QC10 parts for all your core elements, (receivers, bolt, barrel and adjustable buffer system).
Made for- Not Modified. Every QC10 product is engineered specifically for pistol caliber ammunition, not modified from an existing platform, increasing functionality, reliability and overall performance.
Important Warranty Note:
If you intend to register your Quarter Circle 10 firearm as an NFA weapon, test it thoroughly before doing so in a Title 1 Configuration. Once you Form 1 or Form 2 it, you are legally the manufacturer, and we cannot service the firearm. Should your firearm require warranty replacement we can only replace it with a Title I receiver and we are not responsible for tax stamps or NFA fees.
All orders containing a complete pistol must be shipped by 2 Day Air to a licensed, Federal Firearms Dealer (FFL). Please have your FFL email us a copy of their current Firearms license. Orders cannot be shipped without one.
Due to ATF final rule 2021R-08F, all Quarter Circle 10 Full Pistol Builds will no longer come with pistol braces installed or included. Please contact us if you have any questions before ordering.