Centurion Arms E4 ETB Enhanced Dual Ejector Tapered Chrome Bolt Assembly - BLT-E4-CHRM

The E4 bolt assembly features dual ejectors and improved geometry to greatly improve reliability.

The E4 ETB Bolt Assembly from Centurion Arms is a complete bolt assembly for use with your Centurion Arms ‘T’ marked barrels and KAC E3 barrels. The E4 bolt features dual ejectors, ensuring more reliable ejection. This is particularly important for use with suppressors. The bolt geometry also features a larger radius between the lugs and the body to prevent lugs from shearing at their most common failure point.

Features

• Hard chrome
• Dual ejectors for more positive ejection and greater reliability
• Shot-peened
• Magnetic particle inspected
• Tool steel extractor

**Centurion Arms E4/ETB tapered bolts may only be used in Centurion Arms’ T-Marked barrel extensions or Knights Armament E3 barrel extensions. You are solely responsible for checking your Centurion barrel for the “T” marked extension prior to use with E4/ETB bolts (see photo below).  We will not take a returns on misused E4 bolts due to your negligence in confirming your barrel is compatible. 

E4 Bolts will require our “T” marked barrel extensions or the Knights Armament E3 extensions to accommodate the taper lug design. See image below as well as current list of compatible Centurion Arms Barrels.

E4 bolts use standard gas rings for logistical commonality and also use standard extractors with black inserts and either Colt OEM extractor springs or our upgraded 5 coil chrome silica stress relieved spring for ultimate reliability (EXT-SPRING) .

Lastly, our E4 bolts do not require a proprietary cam pin or firing pin as they are designed to support standard pins.  However, they are NOT compatible with KAC’s proprietary E3 firing pins or cam pins.

Currently Compatible T-Marked Centurion Arms Barrels*:

• 2024 Batch of 14.5″ Hammer Forged CarbineSocom Barrels
• 2024 Batch of 11.5″ Hammer Forged Carbine FBI Barrels
• 2024 Batch of  8.5″  Hammer Forged BLK300 Barrels 
• 2024 Batch of  16″   Hammer Forged Midweight Midlength Barrels
• 2024 Batch of  16″   Hammer Forged Lightweight Midlength Barrels
• 2024 Batch of 14.5″ Hammer Forged Enhanced Midlength Socom Barrels
• 2025 Batch of 11.5″ Hammer Forged Lightweight Carbine Barrels
• 2025 Batch of 18″    Stainless Steel MK12 Barrels