The Just Right Carbines Gen 3 is a semi-automatic 9mm pistol caliber carbine built on a one-piece 6061-T6 aluminum receiver. It has a 17-inch threaded barrel under a 13-inch M-LOK handguard, an FDE finish, and feeds from Glock-pattern magazines. The charging handle and ejection port can both be configured for left- or right-handed use, making the carbine fully ambidextrous. 
 

Key Specifications 

• Brand: Just Right Carbines 
• Model: Gen 3 
• Caliber: 9mm 
• Action: Semi Auto 
• Capacity: 17-round 
• Barrel Length: 17" 
• Handguard Length: 13" M-LOK 
• Finish: FDE 
   

Detailed Features 

• Threaded 17-inch barrel accepts a muzzle device 
• Ambidextrous charging handle and ejection port switch to either side 
• Accepts Glock-style magazines instead of a proprietary magazine 
• Picatinny top rail supports mounting a red dot or scope 
• 6-position adjustable stock fits a range of shooter builds

The Gen 3 carries Just Right Carbines' reputation for being one of the few PCC makers that ships a true ambidextrous action, and left-handed owners in particular call that out as the reason they chose it. Build quality gets generally positive marks, with the 6061-T6 receiver holding up to regular range use, though a handful of owners mention the bolt is heavier than an AR-15's and takes some break-in before it runs smoothly.

Ergonomically, the Gen 3 handles more like a rifle than a converted pistol, and the 6-position stock lets shooters adjust length of pull the way they would on an AR platform. The ability to run Glock magazines is a big draw for owners who already carry a Glock, since it means one magazine format across their pistol and carbine.

On value, the Gen 3 sits in an odd spot: pricier than some PCC competitors, but owners who want ambidextrous controls or Glock-magazine compatibility say those two features justify the cost. Aftermarket support is smaller than for AR-15s, though the M-LOK handguard and Picatinny rail mean most standard optics and accessories bolt on without issue.