Knight’s Armament SR-15 E3.2 Bolt Assembly
KAC PN 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. 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.
This is a complete bolt assembly with all internal parts installed. The E3.2 bolt is only compatible with SR-15s and KAC E3 barrel extensions.
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Captain Q (. (verified owner) –
Rooftop Defense is a world class supplier providing access to amazing products. They are reliable, trustworthy and provide excellent shipping . Knights components are as good as they come, the E 3.2 bolt assembly is a welcomed upgrade for enhanced reliability. A BIG thank you!
Gabriel (verified owner) –
Oh sweetie, let’s not pretend all bolts are created equal. The Knight’s Armament SR-15 E3.2 Bolt Assembly isn’t just a bolt—it’s the bolt. The diva. The queen. The standard by which all others should be judged. Period.
First of all, this thing is smoother than a silk robe on marble floors. We’re talking buttery cycling, zero drama, and reliability that would make your favorite Swiss watch blush. You want performance? You want consistency? You want your rifle to run like it knows it’s being watched? This is it.
The proprietary design is doing things most bolts could only dream of. Rounded lugs? Oh yes. Extended life? Absolutely. A extractor setup so good it practically yells “Try me, brass!” every time you hit the range? You better believe it.
Durability? Please. You could run this bolt through a sandstorm, a training course, a bad breakup, and a zombie apocalypse—and it’ll still be saying, “Is that all you got?”
Let’s be real: if you’re running an SR-15 and you’re not using this bolt… why? Like showing up to the Met Gala in cargo shorts. You’re missing the whole point.
This isn’t just a part—it’s a power move.
11/10. She’s strong. She’s reliable. She’s built different.
Now excuse me while I go clean it… just to admire the craftsmanship.
william t. (verified owner) –
As always, blazing shipping. Excellent price. RTD is the best. As for the bolt, KAC quality as always.