The Heckler & Koch Mark 23 is a large-frame semi-automatic pistol chambered in .45 ACP with a 5.87-inch threaded barrel. It has a 10+1 capacity, an OD Green frame, a black slide, and 3-dot sights. 
 

Key Specifications 

• Brand: Heckler & Koch 
• Model: Mark 23 
• Caliber: .45 ACP 
• Action: Semi Auto 
• Capacity: 10+1 
• Barrel Length: 5.87 inches 
• Color/Finish: OD Green frame, Black slide 
   

Detailed Features 

• 5.87-inch threaded barrel 
• OD Green polymer frame with black slide 
• 3-dot sight system 
• 10+1 round capacity in .45 ACP

Owners of the Mark 23 tend to treat it as a collector or range piece rather than a carry gun; the size and weight are a recurring topic, and most buyers go in knowing it is a large-frame pistol by design. Accuracy at distance is consistently praised, and the threaded barrel is a practical feature that suppressor-oriented owners specifically seek out.

The fit and finish on the Mark 23 draw consistent compliments. The OD Green and black color combination is well-liked and the overall build feels substantial. The trigger is generally considered good for the platform, though some shooters note it takes time to get comfortable with the reset.

Value is a genuine debate. The price is at the high end and some owners question whether practical performance justifies the cost compared to other .45 ACP options. Others consider the Mark 23's pedigree and quality worth every dollar, particularly those who sought it out specifically for its design origins.