Evolution Gun Works ISMI 1911 Mainspring (Hammer) 19 lb - 10641

Upgrade the reliability and performance of your 1911 pistol with the Evolution Gun Works ISMI 1911 Mainspring (Hammer) 19 lb. Engineered for shooters who demand consistent ignition and long-term durability, this premium hammer spring delivers smooth, powerful hammer strikes without the inconsistencies of traditional music wire designs.

Key Features and Benefits

• Premium Stainless Alloy Construction – Built from high-grade stainless alloy for superior corrosion resistance, making it ideal for duty, carry, or self-defense applications where exposure to moisture and elements is common.
• Advanced Heat Treatment and Shot Peening – Each spring undergoes precise heat treatment, shot peening, and stress relieving to minimize spring set, enhance consistency, and ensure reliable performance over tens of thousands of cycles.
• 19 lb Rating for Balanced Performance – Provides optimal hammer energy for dependable primer ignition across a wide range of ammunition while maintaining smooth operation in 1911 and 2011 platforms.
• Aerospace-Grade Manufacturing Standards – Produced by ISMI, a U.S. government contractor experienced in high-cycle machine gun springs, guaranteeing exceptional quality and longevity exceeding 100,000 compression cycles in independent testing.

Specifications

• Weight: 19 lb hammer spring rating
• Material: Stainless alloy
• Compatibility: 1911 and 2011 style pistols (full-size and commander models)
• Finish: Corrosion-resistant stainless construction
• Dimensions: Approximately 5.748 in length x 3.268 in width x 0.039 in height

Why Choose the ISMI 19 lb Mainspring?

Traditional mainsprings often suffer from rapid fatigue and inconsistent tension. The ISMI 19 lb mainspring addresses these pain points with advanced materials and processing that promote uniform hammer fall, reduce the risk of light strikes, and extend service life in high-round-count environments. Whether you’re building a custom 1911 or refreshing factory components, this spring offers a direct upgrade for enhanced reliability without compromising trigger feel.

Common Applications

Ideal for competition shooters seeking consistent ignition, law enforcement and defensive users prioritizing corrosion resistance, and custom builders focused on precision parts. Available in additional ratings (17 lb and 22 lb) to fine-tune your setup.

Invest in proven engineering for your 1911 – the ISMI 19 lb Mainspring from Evolution Gun Works delivers the performance and peace of mind serious shooters expect.