Rock Island Armory Rock Ultra MS M1911 4.25″ .45 ACP

About this product

The Rock Island Armory Rock Ultra MS M1911-A1 is a midsize 1911-style semi-automatic pistol chambered in .45 ACP. It pairs a 4.25-inch button-rifled barrel with a parkerized steel frame and a snag-free profile suitable for duty, range work, and practical carry. Factory-installed features include a fiber-optic front sight, a low-profile adjustable rear sight, an ambidextrous safety and a full-length guide rod for consistent function.

Key Specifications

• Chambering is .45 ACP.
• The barrel measures 4.25 inches and is button-rifled.
• Action type is single-action, semi-automatic.
• Finish is black parkerized.
• Frame material is steel.
• Sights are a fiber-optic front paired with an adjustable rear.
• Includes one 8-round magazine.
• Barrel rifling: 6 grooves with a 1:16″ twist.
• Safety features include a thumb ambidextrous safety and an extended beavertail grip safety.
• Slide and controls: serrated slide with skeletonized hammer and trigger.

Designed for shooters who value a robust, feature-rich 1911 in a midsize package, the Rock Ultra MS delivers practical ergonomics and factory upgrades intended to improve handling and sight acquisition. Its combination of traditional 1911 controls and contemporary enhancements makes it a versatile option for range use, duty-oriented roles, or those who prefer a larger-frame defensive pistol.