My Account (Sign in)
Your basket is empty.
0
Basket
contact us by phone Help and contact
Free standard delivery over £199
100-day return policy
My Account (Sign in)
Shopping list
Your basket is empty. (0)
Basket
Newsletter Newsletter
Sale

Over 300,000 customers - we say thank you!

4.93/5 "Very good" (1400+ reviews)

40,000+ products for hunting and shooting sports

Home Rifle Parts Receiver Parts Recoil Parts Recoil Springs SPRINCO USA M4 CARBINE CS REDUCED POWER SPRING KITS Support
Sierra Sale!
Enhance your M4 with the Sprinco USA Reduced Power Spring Kit! 🌟 Perfect for low power training and improved reliability.

SPRINCO USA M4 CARBINE CS REDUCED POWER SPRING KITS - SPRINCO USA REDUCED POWER KIT BUFFER 4-COIL BOLT EXTRACTOR SPRING

657780251490 943000043

Variations:

Enhance your M4 with the Sprinco USA Reduced Power Spring Kit! 🌟 Perfect for low power training and improved reliability.
SPRINCO USA REDUCED POWER KIT BUFFER 4-COIL BOLT EXTRACTOR SPRING
39.9 GBP 0 £39.90 *
Product no.: 943000043
Backorderable
39.9 GBP 0 £39.90 *
Ask question
Enhance your shooting experience with the M4 Carbine Reduced Power Spring Kit from Sprinco USA. Perfect for training operations! ✨
SPRINCO USA REDUCED POWER KIT BUFFER XP 5-COIL BOLT EXTRACTOR SPRING
39.9 GBP 0 £39.90 *
Product no.: 943000042
Backorderable
39.9 GBP 0 £39.90 *
Ask question
Upgrade your M4 Carbine with the Sprinco Reduced Power Spring Kit! 🌟 Enjoy smoother operation and enhanced reliability for training and performance.
SPRINCO USA M4 CARBINE REDUCED POWER BUFFER SPRING
36.9 GBP 0 £36.90 *
Product no.: 943000044
Backorderable
36.9 GBP 0 £36.90 *
Ask question
36.9 39.9 3 GBP
39.9 GBP £39.90

Prices inclusive of duty & VAT.

Product no.: 943000043

Mfr. No.: 25149

657780251490 Reduced Power Buffer Spring. Sprinco collaborated with two prominent commercial ammunition manufacturers and two prominent gunsmiths to arrive at the design for the Yellow spring. It’s approximately 20% lighter than the White spring, and was the consensus choice out of 4 different evaluation samples provided to all parties. They all added in their final evaluations that if a particular gun needed a lighter spring, that the gas port should be enlarged for overall reliability. The Yellow spring is also appropriate for with low power SRTA training or SIMS Rounds for training operations.
Backorderable
Be the first to rate this product
1
2
3
4
5
6
7
8
9
10+
Wish List Ask question

Variations:

Enhance your M4 with the Sprinco USA Reduced Power Spring Kit! 🌟 Perfect for low power training and improved reliability.
SPRINCO USA REDUCED POWER KIT BUFFER 4-COIL BOLT EXTRACTOR SPRING
39.9 GBP 0 £39.90 *
Product no.: 943000043
Backorderable
39.9 GBP 0 £39.90 *
Ask question
Enhance your shooting experience with the M4 Carbine Reduced Power Spring Kit from Sprinco USA. Perfect for training operations! ✨
SPRINCO USA REDUCED POWER KIT BUFFER XP 5-COIL BOLT EXTRACTOR SPRING
39.9 GBP 0 £39.90 *
Product no.: 943000042
Backorderable
39.9 GBP 0 £39.90 *
Ask question
Upgrade your M4 Carbine with the Sprinco Reduced Power Spring Kit! 🌟 Enjoy smoother operation and enhanced reliability for training and performance.
SPRINCO USA M4 CARBINE REDUCED POWER BUFFER SPRING
36.9 GBP 0 £36.90 *
Product no.: 943000044
Backorderable
36.9 GBP 0 £36.90 *
Ask question

Description:

Reduced Power Buffer Spring. Sprinco collaborated with two prominent commercial ammunition manufacturers and two prominent gunsmiths to arrive at the design for the Yellow spring. It’s approximately 20% lighter than the White spring, and was the consensus choice out of 4 different evaluation samples provided to all parties. They all added in their final evaluations that if a particular gun needed a lighter spring, that the gas port should be enlarged for overall reliability. The Yellow spring is also appropriate for with low power SRTA training or SIMS Rounds for training operations.

Top takeaways

  1. The Yellow spring is approximately 20% lighter than the White spring, designed in collaboration with ammunition manufacturers and gunsmiths.
  2. For guns requiring a lighter spring, it's recommended to enlarge the gas port for better reliability.
  3. The Yellow spring is suitable for low power SRTA and SIMS Rounds in training operations.

Attributes

  • Delivery weight: 0.077kg
  • Shipping height: 25mm
  • Shipping width: 25mm
  • Shipping length: 337mm
  • UPC: 657780251490

Item details

Made in USA

Customers reviews

Customer ratings (0)

0 / 5

Customers also bought

Oops! Something went wrong.

We encountered an error while loading this content. Please refresh the page to continue. If the issue persists, contact our customer support.

Site Navigation
Product Categories
Ordering
Customer Service

Welcome!

to Brownells UK, your destination for anything gun related. With our roots in a genuine passion for firearms, we bring you an unmatched selection of Gun Parts, Firearm Accessories, Gunsmithing Tools, Scopes & Red Dot Sights and Expert Knowledge.

Whether you're looking to maintain, repair, or upgrade, we've got what you need!

For Shooters, By Shooters
We share your enthusiasm and know exactly what you're looking for because we're part of the community.

Massive Selection
From the essentials to the unique, find everything under one roof.

Our blend of tradition and innovation
Shop with the convenience of modern technology, backed by a legacy of experience.

Browse our collection and discover why we're the trusted name in shooting sports & hunting.

Brownells Norge - Komplett utvalg av ladeutstyr, våpendeler, kuler, hylser, kikkerter, optikk og luftvåpen Brownells Österreich - Einer der größten Lieferanten für Waffenteile, Büchsenmacherzubehör & Schießsportzubehör Brownells Switzerland - Einer der größten Lieferanten für Waffenteile, Büchsenmacherzubehör & Schießsportzubehör Brownells Deutschland - Einer der größten Lieferanten für Waffenteile, Büchsenmacherzubehör & Schießsportzubehör Brownells France - Le plus grand fournisseur d'Accessoires pour le tir, Pièces détachées & Outils d'Armurier Brownells Iberica - El mayor proveedor de accesorios para el Tiro, Piezas y herramientas del armero. Brownells Sverige - Världens största leverantör av Vapendelar, Vapensmide Verktyg & Skyttetillbehör Brownells Suomi Brownells Italia - Il negozio del più grande rivenditore di componenti e accessori per armi da tiro, difesa e caccia Brownells Polska - Największy na świecie dostawca części broni, narzędzi rusznikarskich & akcesoriów strzeleckich Brownells Česko - Největší světový dodavatel součástí zbraní, střeleckého příslušenství a zbrojního nářadí
*
Prices inclusive of duty & VAT.

© 2025 Brownells UK
Part of the Brownells Europe Group

Logo Brownells
Classical viewClassical view Mobile viewMobile view
Back to top