When considering the purchase of a used Heckler & Koch Mark 23 chambered in .45 ACP, it's essential to understand the specifications and features of this iconic pistol. Here are the details about a used Heckler & Koch Mark 23 in .45 ACP:

- Model: Heckler & Koch Mark 23 (MK23)
- Caliber: .45 ACP
- Action: Semi-automatic, double-action/single-action (DA/SA)
- Capacity: 12 rounds in a detachable box magazine
- Barrel Length: 5.87 inches
- Overall Length: 9.65 inches
- Weight: Approximately 2.43 lbs (39 oz) unloaded
- Frame: Polymer frame with a steel slide
- Sights: Fixed iron sights for durability and precision shooting
- Safety: Ambidextrous safety and decocking levers for enhanced safety
- Finish: Black or tan finish options available

The Heckler & Koch MK23 is a highly reliable and accurate combat pistol designed for military use, popularized by its robust construction, accuracy, and exceptional durability. The pistol's ergonomics, enhanced recoil reduction, and exceptional accuracy make it a sought-after handgun for those seeking a premium quality firearm.

When inspecting a used Heckler & Koch MK23, ensure you check the overall condition, including the bore, frame rails, and internals. Verify the functionality of the safety mechanisms, trigger, and magazines. It's advisable to have a gunsmith inspect the firearm for any potential issues before making a purchase.

If you have any specific questions or need further details about the used Heckler & Koch MK23 .45 ACP pistol, feel free to ask!