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Home Handgun Parts Frame Parts Mainspring Parts Mainsprings ISMI 1911 MAINSPRING Support
Easter Sale up to 60%
Upgrade your 1911 with the ISMI 15 lb. mainspring for reliable performance and a lighter trigger pull. 💪 Built to aerospace specs!

ISMI 1911 MAINSPRING - ISMI 15 LB. C/S SPRING

445004014

Variations:

-10 %
Upgrade your 1911 with the ISMI 15 lb. mainspring for reliable performance and a lighter trigger pull. 💪 Built to aerospace specs!
ISMI 15 LB. C/S SPRING
17 GBP 33 £17.00 * £18.90
In stock
Product no.: 445004014
In stock
17 GBP 33 £17.00 * £18.90
Ask question
-10 %
Upgrade your 1911 with the ISMI 17 lb. mainspring for a lighter trigger pull and reliable performance. 💪 Durable and corrosion-resistant!
ISMI 17 LB. C/S SPRING
17 GBP 27 £17.00 * £18.90
In stock
Product no.: 445105017
In stock
17 GBP 27 £17.00 * £18.90
Ask question
-10 %
Upgrade your 1911 with the ISMI 19 lb. mainspring for reliable performance and durability. 💪 Perfect for a consistent trigger pull!
ISMI 19 LB. S/S SPRING, EACH
17 GBP 2 £17.00 * £18.90
In stock
Product no.: 445105191
In stock
17 GBP 2 £17.00 * £18.90
Ask question
-10 %
Upgrade your 1911 with the ISMI 22 lb. mainspring for reliable performance and durability. 💪 Perfect for Government and Commander models!
ISMI 22 LB. 1911 S/S SPRING, EACH
17 GBP 15 £17.00 * £18.90
In stock
Product no.: 445000023
In stock
17 GBP 15 £17.00 * £18.90
Ask question
-10 %
Upgrade your 1911 with ISMI's 19 lb. mainspring for a smooth trigger pull and reliable performance. 💪 Built to aerospace specs!
ISMI 19 LB. S/S SPRING, 5-PAK
Not available
Product no.: 445105195
Not available
31.4 GBP 0 £31.40 * £34.90
Ask question
18.9 18.9 5 GBP
Sale
17 GBP £17.00 £18.90

Prices inclusive of duty & VAT.

Product no.: 445004014

Mfr. No.: 15MS

CAD designed and built to Aerospace specifications from chrome silicon, corrosion resistant, stainless steel or chrome vanadium for maximum durability, consistency and reliable performance. Built to aerospace specifications; heat treated, shot peened and fully stress relieved to minimize spring set. 1911 AUTO MAINSPRING - Stainless steel (SS) or chrome silicon (CS); wound in the very popular 19 lb. and 17 lb. rate for lighter, consistent trigger pull with reliable ignition.
In stock
2

Delivery time approx. 7-14 days.
More than 10 pieces in USA warehouse

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Delivery time approx. 7-14 days.
More than 10 pieces in USA warehouse

Wish List Ask question

Variations:

-10 %
Upgrade your 1911 with the ISMI 15 lb. mainspring for reliable performance and a lighter trigger pull. 💪 Built to aerospace specs!
ISMI 15 LB. C/S SPRING
17 GBP 33 £17.00 * £18.90
In stock
Product no.: 445004014
In stock
17 GBP 33 £17.00 * £18.90
Ask question
-10 %
Upgrade your 1911 with the ISMI 17 lb. mainspring for a lighter trigger pull and reliable performance. 💪 Durable and corrosion-resistant!
ISMI 17 LB. C/S SPRING
17 GBP 27 £17.00 * £18.90
In stock
Product no.: 445105017
In stock
17 GBP 27 £17.00 * £18.90
Ask question
-10 %
Upgrade your 1911 with the ISMI 19 lb. mainspring for reliable performance and durability. 💪 Perfect for a consistent trigger pull!
ISMI 19 LB. S/S SPRING, EACH
17 GBP 2 £17.00 * £18.90
In stock
Product no.: 445105191
In stock
17 GBP 2 £17.00 * £18.90
Ask question
-10 %
Upgrade your 1911 with the ISMI 22 lb. mainspring for reliable performance and durability. 💪 Perfect for Government and Commander models!
ISMI 22 LB. 1911 S/S SPRING, EACH
17 GBP 15 £17.00 * £18.90
In stock
Product no.: 445000023
In stock
17 GBP 15 £17.00 * £18.90
Ask question
-10 %
Upgrade your 1911 with ISMI's 19 lb. mainspring for a smooth trigger pull and reliable performance. 💪 Built to aerospace specs!
ISMI 19 LB. S/S SPRING, 5-PAK
Not available
Product no.: 445105195
Not available
31.4 GBP 0 £31.40 * £34.90
Ask question

Description:

Designed For Maximum Consistency & Reliability
CAD designed and built to Aerospace specifications from chrome silicon, corrosion resistant, stainless steel or chrome vanadium for maximum durability, consistency and reliable performance. Built to aerospace specifications; heat treated, shot peened and fully stress relieved to minimize spring set. 1911 AUTO MAINSPRING - Stainless steel (SS) or chrome silicon (CS); wound in the very popular 19 lb. and 17 lb. rate for lighter, consistent trigger pull with reliable ignition.

SPECS: Chrome silicon or stainless steel round wire, chrome vanadium flat wire.

Top takeaways

  1. The ISMI 1911 Mainspring is crafted from corrosion-resistant materials such as chrome silicon and stainless steel, adhering to Aerospace specifications for durability and performance.
  2. Designed for the 1911 AUTO with specific models including Government and Commander, the mainspring is available in popular 19 lb. and 17 lb. rates for a lighter and consistent trigger pull.
  3. Each spring is heat treated, shot peened, and stress relieved to reduce spring set and ensure maximum reliability.

Attributes

  • Model: Commander,Government
  • Weapon type: 1911
  • Delivery weight: 0.005kg
  • Shipping height: 8mm
  • Shipping width: 80mm
  • Shipping length: 134mm

Item details

Made in USA

Customers reviews

Customer ratings (2)

3 / 5
Not recommended

Brownells USA Too weak... 09/03/2015

this ISMI 15 lb mainspring is so weak cannot ignite the primers…15lb of Wolff is way better and would ignite any primers….I have 3 and its still sitting gathering dust….

Definitely recommended

Brownells USA GOOD BUY! 28/01/2014

I used this in conjuction with an 18.5 lb recoil spring in a High Standard 1911, Also used a Wilson Combat hammer and sear. This mainspring will lighten your trigger pull, seems to be of good quality.

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