The Rock Island Armory STK100 is a striker-fired 9mm Luger handgun with a lightweight aluminum frame and black Parkerized finish. At 1.8 lbs. and 10+1 capacity, it covers range shooting, home defense, and everyday carry. 
 

Key Specifications 

• Brand: Rock Island 
• Model: STK100 
• Caliber: 9mm Luger (9x19 Para) 
• Action: Striker Fire 
• Capacity: 10+1 rounds 
• Barrel Length: 4.5 inches 
• Weight: 1.8 lbs. 
• Finish: Black Parkerized 
• Frame Material: Aluminum 
   

Detailed Features 

• Striker-fired action produces a consistent trigger pull on every shot. 
• Aluminum frame holds weight to 1.8 lbs. for extended carry. 
• Black Parkerized finish resists wear and corrosion across different environments. 
• Sight setup: tenon cut front sight with fixed optic cover rear sight.

The Rock Island STK100 gets solid marks on accuracy and value, with some reliability concerns worth noting before buying.

Range performance and accuracy are praised consistently. The striker-fired trigger pull is smooth and predictable, and the ergonomics work well for extended sessions — comfortable grip and accessible controls. The price-to-feature ratio comes up often; many buyers find it delivers full-size 9mm capability at a price point that undercuts comparable options.

On the negative side, reliability problems are the most common complaint, especially early in ownership or with certain ammunition types. A few users find the weight less ideal for concealed carry compared to lighter options. As with most firearms, individual experiences vary based on preferences and use case, but the reliability reports appear in enough reviews to be a real consideration.