A few years ago Quarter Circle 10 came out with their QC5. It is an 9mm AR receiver set that can take MP5 magazines. Well with the help of my friend Sean St. Cin they have refocused their brand and will be coming out with their QC10 MP-5 inspired YKMF-5.

Quarter Circle 10 @ TFB

• [TriggrCon 2019] ALL the SIG Mags! Quarter Circle 10 P320 PCC in 9mm
• [SHOT 2019] Quarter Circle 10 Pistol Caliber Carbines
• Quarter Circle 10 – QC5 Receiver set for MP5 9 mm magazines

While the QC5 receiver set is not new, the YKMF-5 is. In the past, QC10 offered the QC5 as a sort of hybrid between an AR-9 and MP5. The aesthetics were more AR-9 than MP5. With the help of Sean, the YKMF-5 looks more like an MP5. The YKMF-5 is still a direct blowback AR.

To help with the YKMF-5 aesthetics they switched to a new style handguard that is inspired by the classic MP5 wide handguard.

The handguard is machined aluminum. The barrel is 5.5 inches long and it comes with a Dead Air Keymo muzzle brake so you can attach suppressors to it. They opted for Reptilia Corp CQC grip and an SB Tactical PDW brace.

For controls it will come with a Phase 5 ambidextrous safety selector.

Another major change for the QC5 to be a YKMF-5 is the upper receiver. The original QC5 upper used an AR-15 charging handle. QC10 opted for a side charging upper on this new iteration of the QC10 MP5.

The HK416 sights do not come with the YKMF-5. It will retail for $1700. They are looking at possibly reducing this price and are planning for an MP5-SD styled variant and some other MP5 styled variants. They have sent one to me for a review so look out for that soon after SHOT Show.

They are streamlining their catalog. They are phasing out their P226 AR-9 to go with their P320 magazine fed version. They will, however, still make Colt/UZI mag and Glock mag versions of their PCC.

A small pet project for Sean is to support shooters in California so they will have a California compliant PC carbine.