The Maxim Defense CPS MD9 is a semi-automatic pistol/PDW chambered in 9mm Luger with a 5.5-inch barrel, Glock-compatible 25-round magazine, and an overall length of 20 inches with the Maxim CQB stock. The forged 7075-T6 aluminum receiver and black nitride barrel are paired with the Maxim Hate Brake muzzle device. 
 

Key Specifications 

• Brand: Maxim Defense 
• Model: CPS MD9 
• Caliber: 9mm Luger 
• Action: Semi-Auto 
• Barrel Length: 5.5 inches 
• Overall Length (OAL): 20 inches 
• Capacity: 25 rounds (Glock compatible) 
• Weight: 6 lbs 
• Stock Material: Synthetic with Maxim CQB stock 
• Grip Material: Black Polymer 
• Receiver Material: Forged 7075-T6 Aluminum 
• Sights: Optic Ready 
• Muzzle Device: Maxim Hate Brake 
• Finish Details: 
  • Barrel Finish: Black Nitride 
  • Receiver Finish: Black Anodized 
     

Detailed Features 

The Glock-compatible magazine system means 25-round magazines are widely available. The optic-ready design has no fixed sights, so you'll want to add optics or irons before shooting. The Hate Brake reduces muzzle rise during rapid fire, which matters when you're running 25 rounds. 
 
The M-LOK handguards give you attachment points for lights and accessories. At 20 inches overall and 6 lbs, this is closer to a PDW or short carbine than a conventional handgun -- it's not a pocket gun. 
 

Target Audience 

Shooters who want a high-capacity 9mm on an AR-style platform -- competitors in pistol caliber carbine divisions, home defense buyers who prioritize capacity, or collectors who appreciate the PDW format. 
 

Usage Scenarios 

• Pistol caliber carbine competition where 25-round capacity reduces reloads 
• Home defense with 9mm in a more controllable platform than a standard handgun 
• Range use and training where the ergonomics and optic-ready design support practice

The Maxim Defense CPS MD9 draws a specific buyer -- people who want a 9mm on an AR chassis with high capacity -- and reviews tend to reflect whether buyers matched their expectations to the platform.

The 25-round Glock-compatible magazine capacity is consistently praised. Less time spent reloading means more time shooting, which matters for competition or sustained training sessions.

Build quality feedback is positive. The forged 7075 aluminum receiver and Maxim's fit and finish receive good marks, and the ergonomics of the grip and handguard are comfortable during extended shooting.

Recoil is mild for a 9mm of this size, and the Hate Brake does what it's supposed to -- keeping muzzle rise down during rapid strings.

Price is the main concern. Maxim Defense products carry a premium, and some buyers question whether the CPS MD9 offers enough over other PCCs at lower price points. Owners who've shot it generally defend the build quality as justifying the cost; those doing spec comparisons sometimes disagree.

Availability of the specific Maxim accessories and magazines comes up occasionally as a practical limitation.