The HK USP45 Compact V1 is a DA/SA .45 ACP pistol with an 8+1 capacity, 3.78-inch polygonal-rifled barrel, night sights, and a decocker safety. It's the compact version of the USP45, keeping the same caliber in a shorter, lighter package. 
 

Key Specifications 

• Brand: HK 
• Model Name: USP45 Compact (V1) 
• Caliber: .45 ACP 
• Action Type: Double/Single Action (DA/SA) 
• Capacity: 8+1 rounds 
• Barrel Length: 3.78 inches 
• Weight: 28.16 oz (1.76 lbs) 
• Finish: Black 
• Frame Material: Polymer 
• Grip Type: Black Polymer 
• Sights: Fixed Night Sights 
   

Features 

 
The polygonal rifling on the 3.78-inch barrel provides good gas sealing and bore life. Night sights are fixed-style, no adjustment required, good visibility in low-light. The decocker safety lets you lower the hammer manually without engaging the trigger, which is the safety-conscious approach for DA/SA carry. The modular grip system uses ergonomic polymer panels. At 28.16 oz, it's heavier than polymer striker-fired options at this size, which is a tradeoff with .45 ACP in a compact frame.

Users consistently praise the USP45 Compact for build quality and the confidence that comes with HK construction. Night sights are well-regarded for low-light use. Ergonomics and grip comfort get positive feedback, and the decocker safety is appreciated for the added safety margin.

.45 ACP recoil in this compact frame is a frequent discussion point. Most users manage it well but it's worth noting. Size and weight versus competing compact .45 options comes up for concealed carry considerations. Pricing relative to other compact .45 pistols is mentioned, with most users feeling quality justifies the cost while some explore alternatives.