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Evolution Gun Works Main Hammer Spring ISMI Up to 24% Off — 4 models

Evolution Gun Works Main Hammer Spring ISMI, 17 lb, 10640
Evolution Gun Works Main Hammer Spring ISMI, 19 lb, 10641
Evolution Gun Works Main Hammer Spring ISMI, 22 lb, 10642
Evolution Gun Works Main Hammer Spring ISMI Officers Model, 23 lb, 10643
Evolution Gun Works Main Hammer Spring ISMI, 17 lb, 10640
1 of 4 images
Evolution Gun Works Main Hammer Spring ISMI, 17 lb, 10640
Evolution Gun Works Main Hammer Spring ISMI, 19 lb, 10641
2 of 4 images
Evolution Gun Works Main Hammer Spring ISMI, 19 lb, 10641
Evolution Gun Works Main Hammer Spring ISMI, 22 lb, 10642
3 of 4 images
Evolution Gun Works Main Hammer Spring ISMI, 22 lb, 10642
Evolution Gun Works Main Hammer Spring ISMI Officers Model, 23 lb, 10643
4 of 4 images
Evolution Gun Works Main Hammer Spring ISMI Officers Model, 23 lb, 10643

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  • Evolution Gun Works Sear Spring, 1911 Colt, Blue, 10690
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Product Info for Evolution Gun Works Main Hammer Spring ISMI

Available in 17lb or 19lb. All ISMI Springs are made from silicone chrome instead of 150 year old music wire. Every ISMI spring is heat treated, shot peened & stress relieved to enhance durability, consistency and reliability. ISMI is a contractor of the U.S. government and produces springs used in machine guns with incredibly high cycling rates. Also, the creator of ISMI springs obtained his knowledge from extensive research in the development of springs used in Indy car racing.image

Specifications for Evolution Gun Works Main Hammer Spring ISMI:

Manufacturer: Evolution Gun Works
Color: Black

Package Contents:

  • Evolution Gun Works Main Hammer Spring ISMI

What firearm models does the manufacturer say Evolution Gun Works Main Hammer Spring ISMI is compatible with?

The manufacturer suggests that Evolution Gun Works Main Hammer Spring ISMI is compatible with Colt Officer's ACP

Evolution Gun Works Main Hammer Spring ISMI Orderable Models

List of Orderable Models

  • Evolution Gun Works Main Hammer Spring ISMI, 19 lb, 10641 , MPN: 10641 , UPC: 841370101252 , Code: KK-PDC-MHMSP-10641
  • Evolution Gun Works Main Hammer Spring ISMI, 22 lb, 10642 , MPN: 10642 , UPC: 841370114665 , Code: KK-PDC-MHMSP-10642
  • Evolution Gun Works Main Hammer Spring ISMI, Officers Model, 23 lb, 10643 , MPN: 10643 , UPC: 841370114672 , Code: KK-PDC-MHMSP-10643
  • Evolution Gun Works Main Hammer Spring ISMI, 17 lb, 10640 , MPN: 10640 , UPC: 841370101245 , Code: KK-PDC-MHMSP-10640
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Last updated 2026-09-15 UTC.