KAC-Knight's Armament SR-15 E3.2 Bolt Assembly

Knight's Armament
Current Stock:

Out of stock

Out of Stock

KAC-Knight's Armament SR-15 E3.2 Bolt Assembly (122054)

The SR-15 E3.2 Enhanced Bolt features a number of components designed to exceed expectations for durability and service life, even when exposed to extreme and unrelenting conditions. Dual ejectors considerably mitigate wear and prolong lifespan compared to the legacy single ejector, delivering sustained ejection force to the case head due to strategic ejector placement. A vibration-dampening o-ring works synergistically with the extractor, ensuring a constant and positive force of the extractor claw against the case rim throughout the extraction and ejection processes. Stress relief features incorporated into the lugs significantly extend the service life. Its radiused lugs and reduced diameter cam pin hole render it the most durable AR-pattern bolt known to date. The dual-spring extractor, featuring improved leverage, adeptly resolves extractor durability and operational issues commonly encountered with short-barreled carbines. It is a proprietary bolt designed specifically for use in SR-15 and SR-16 rifles.

E3.2 Enhanced Bolt Features
Dual Ejectors – Provides more positive ejection for increased reliability with suppressors.
Enlarged Bolt Face – Provides more positive engagement in the chamber and ensures proper seating upon cycling.
Rounded Bolt Lugs – Less prone to chipping or cracking than traditional square lug designs.
Reduced-Size Cam Pin – Allows for a thicker bolt web, strengthening a common failure point in the AR-15 bolt design.
Enhanced Reliability Extractor – Shaped like a “T” this extractor’s pivot point is shifted forward to apply constant pressure on the case rim and reduce extraction failures. Its dual extractor springs provide a fail safe in the event that one fails during hard usage.

The E3.2 bolt is only compatible with SR-15s and KAC E3 barrel extensions.


Package Contents:


  • E3.2 Bolt
  • Firing Pin
  • Cam Pin
  • Spare Extractor Springs
  • Spare Extractor O-Ring