Free Shipping & Free Returns*

FREE SHIPPING on Over 250,000 Products

Enjoy free shipping during the holidays! Shop now and get Free Value Shipping on most orders over $49 to the contiguous 48 states, DC and to all U.S. Military APO/FPO/DPO addresses.

Enjoy Our Extended FREE RETURNS

We want to ensure that making a return is as easy as possible! With our Hassle-Free, Extended Holiday Returns, eligible orders placed from November 12, 2025 on will benefit from an extended return deadline (January 13, 2026 or 30 days after receipt of your order - whichever is later). We'll even cover the cost of return shipping. Learn more about our Return Policy.

Shopping Cart
Questions & Answers
Are these 5.56/300 Blackout? Side or down vent?

I’m inclined to believe the BCGs are 5.56/300BLK given the price comparison to KAK’s website and when I purchased my PVD-coated BCG it was 5.56/300BLK.

by Jordan, Verified Owner, July 7, 2025
Will this BCG fit a mil spec ar-15 Expert Answer

Yes, the KAK Industry K-SPEC Enhanced Bolt Carrier Group is compatible with any Mil-spec AR15.

by Ethan, Gear Expert, October 1, 2025
Customer Reviews
Most Recent Reviews
Great BCG tight specs by RoninKW, Verified Owner, June 21, 2025
This is a great BCG it came well lubded. On arrival I looked it over then tore it down to inspect it in detail. Couldn't find any faults with the product design and assembly. I took it down for a short range trip with suppressed 300 subs and supers ...
Read More...
Read 1 Review
Color: NP3 Finish: NP3 Caliber: 7.62x39mm Gun Make: AR Platform Gun Model: AR-15 Condition: Factory DEMO Additional Features: Down Vent

Code: 3KE-BCG-K-SPECF-425-0506-007-DEMO

MPN: 425-0506-007-DEMO

Final Sale
$215.99

Product Info for KAK Industry K-SPEC Enhanced Low Mass AR-15 5.56mm/.300 AAC Blackout Bolt Carrier Group

The K-SPEC BCG combines multiple key features focused on increasing the reliability of your AR15 style firearm no matter if you are running suppressed or unsuppressed, and regardless of conditions. The K-SPEC is a truly plug and play BCG that will accommodate whatever configuration your mission requires.image

For those running suppressed, the K-SPEC requires no additional tuning or tweaking of the gas or recoil systems to run reliably. Like all KAK BCGs, the K-SPEC is machined to the M16 full auto profile.

Specifications for KAK Industry K-SPEC Enhanced Low Mass AR-15 5.56mm/.300 AAC Blackout Bolt Carrier Group:

Manufacturer: KAK Industry
Color: NP3
Finish: NP3
Carrier Material: 8620 Steel
Bolt Material: 9310 Steel
Caliber: 7.62x39mm
Gun Make: AR Platform
Gun Model: AR-15
Condition: Factory DEMO
Additional Features: Down Vent

Features of KAK Industry K-SPEC Enhanced Bolt Carrier Group:

  • Reduced Peak DB Report
  • When used in conjunction with a silencer, the gas redirect produces a quieter report
  • Slotted Angled Carrier Rails - For enhanced functionality in adverse and rugged conditions such as sand, mud, dirt, and grime. These rail cuts are designed for debris disbursement, resulting in ultra-high functionality in the toughest conditions, including suppressor fouling and foreign contaminates. Strategically located angle cuts in the rails result in fouling and debris being moved into noncritical areas that are not in contact with the receiver and do not affect the function of the firearm. aka sandcutter
  • Downward Gas Vents - In an effort to reduce the amount of debris and gas vented towards the shooters face, the two standard gas relief ports have been relocated from the ejection port side of the K-SPEC carrier and placed underneath, in the magazine feed lip channels. Two additional emergency relief ports have also been added to the bottom of the carrier to mitigate structural damage in the event of a case head separation. Testing has shown that venting the gasses through the magazine well has no negative impact on the feeding or function of the magazine nor ammunition, and any added heat is negligible.
  • Dual ejectors - The K-SPEC dual ejector system uses mil-spec ejectors and springs that require no proprietary parts. Ejector holes are centered on the lugs to avoid any reduction in strength of the bolt. The dual ejector system increases the ejection reliability and adds consistency to the ejection pattern. AS Industry has been manufacturing dual ejector bolts for the AR10/LR308 platform for over a decade and has used that experience to create a durable and reliable dual ejector system for the AR15 platform.

Package Contents:

  • KAK Industry K-SPEC Enhanced Low Mass AR-15 5.56mm/.300 AAC Blackout Bolt Carrier Group

KAK Industry K-SPEC Enhanced Low Mass AR-15 5.56mm/.300 AAC Blackout Bolt Carrier Group Orderable Models

List of Orderable Models

  • DEMO, KAK Industry K-SPEC Enhanced Bolt Carrier Group AR-15, 7.62x39mm, Dual Ejector, Down Vent, Sand Cuts, NP3, 425-0506-007 , MPN: 425-0506-007-DEMO , Code: 3KE-BCG-K-SPECF-425-0506-007-DEMO

KAK Industry K-SPEC Enhanced Low Mass AR-15 5.56mm/.300 AAC Blackout Bolt Carrier Group Unavailable & Discontinued Models

List of Unorderable Models

  • USED, KAK Industry K-SPEC Enhanced Bolt Carrier Group AR-15, 5.56/ 300 Blackout, Dual Ejector, Down Vent, Sand Cuts, Black, Phosphate, 425-0512-003-EDEMO-US-B , MPN: 425-0512-003-EDEMO , Code: 3KE-BCG-K-SPECF-425-0512-003-EDEMO-US-B
  • USED, KAK Industry K-SPEC Enhanced Bolt Carrier Group AR-15, 5.56/ 300 Blackout- Dual Ejector, Down Vent, Sand Cuts, FDE PVD, 425-0507-003 , MPN: 425-0507-003-EDEMO , Code: 3KE-BCG-K-SPECF-425-0507-003-EDEMO-DF-C
  • DEMO, KAK Industry K-SPEC Enhanced Bolt Carrier Group , MPN: 425-0506-003-DEMO , Code: 3KE-BCG-K-SPECF-425-0506-003-DEMO
  • KAK Industry K-SPEC Enhanced Low Mass AR-15 5.56mm/.300 AAC Blackout Bolt Carrier Group, 7075 Aluminum, NP3, Gold, 425-0605-001 , MPN: 425-0605-001 , UPC: 811163035682 , Code: 3KE-BCG-K-SPECF-425-0605-001
  • KAK Industry K-SPEC , MPN: 425-3306-009 , Code: 3KE-BCG-K-SPECF-425-3306-009
Compare (0)