Sharps Xtreme Performance Bolt (XPB) Carrier Group Complete in NiB-X (Nickel Boron)


Sharps Xtreme Performance Bolt (XPB) Carrier Group Complete in NiB-X (Nickel Boron)

$249.99 $199.99

(9 customer reviews)

The Sharps Xtreme Performance Bolt (XPB) Carrier Group Complete is comprised of our patented Relia-bolt, and our Balanced Bolt Carrier. Both Balanced Carrier and the Relia-Bolt are coated in NIB-X (Nickel Boron).


Available on backorder

SKU: SRCXPBCG-NIBX Categories: , ,



The Sharps Xtreme Performance Bolt (XPB) Carrier Group Complete is comprised of our patented   Relia-Bolt™ and our Balanced Bolt Carrier. Both are machined out of S7 tool steel. The XPB undergoes a 24-hour thermal cycle proprietary heat treatment and is finished with NiB-X (Nickel Boron) Coating.  The XPB carrier displays the SRC logo machine cut and is visible when the ejection port door is open. The XPB fits standard AR-15/M16/M4 rifles chambered in .223/5.56, Sharps 25-45, and 300 Blackout calibers.

Color: Silver

We offer a 30-Day Money Back Guarantee on our complete line of Sharps bolt and bolt carrier products.

Limited Lifetime Warranty

If any Relia-Bolt™ is found to have defects in materials or workmanship, SRC will repair or replace it at no charge.


Technical Data
Bolt: S7 Tool steel, shot peened NiB-X coated (U.S. Patent No. 9,863,729)
Bolt Carrier:
S7 Tool steel, shot peened and NiB-X coated
Gas Key: 4130 Steel, attached with Grade 8 hardware, properly staked and NiB-X Coated
Cam Pin: 4340 Steel, Manganese Phosphate coated
Firing Pin: Mil Spec firing pin made of 8740 steel, center‐less ground and Hard Chrome coated
Extractor: 4340 Steel, NiB-X coated
Ejector: S7, shot peened and Manganese Phosphate coated
Extractor Pin: S7, shot peened and Manganese Phosphate coated
Mil-Spec Ejector Springs, Firing Pin Retaining Pin, Gas Rings

Batch MPI and HPT tested
Tensile strengths of 1550-1600 mpa, or 220,000-235,000 psi.
Toughness of over 200 ft./lb. Charpy C-Notch
HRC of 46 yields a 15% increase in hardness at the same toughness comparing to Carpenter 158 & 9310

NiB-X Coating:
Specifically engineered NiB-X nickel boron coating to provide long life, high reliability and easy cleaning and maintenance. The BCG components are coated and polished to reduce fouling adherence. Coating is guaranteed for life against chipping, spalling or flaking. Over 30K rounds in Government protocol endurance testing did not wear the coating off. Especially beneficial in short barrel setups and suppressed platforms.
Hardness HV 0.05: HRC 70+
Friction vs Dry Steel 0.1
Color: Hyper Silver (Polished)

Additional information

Weight 11.20 oz

9 reviews for Sharps Xtreme Performance Bolt (XPB) Carrier Group Complete in NiB-X (Nickel Boron)

  1. Brian Matlock (verified owner)

    Converted all my AR’s to the XPB, the NiB-X just makes it a dream to clean. IMO it’s a go to war BCG. Very impressed.

  2. Michael Dague (verified owner)

    This is my second Sharps bolt and bolt carriage, when shooting 3 gun fraction of seconds count the Sharps bolt and bolt carriage cycle faster and softer then the average system allowing to get back on target quicker saving you time.
    The bonus is cleaning is a breeze, no scraping or soaking in solvent just wipe off, lubes and go.

  3. Kelly Kendall (verified owner)


  4. Eric Frisch (verified owner)

    I have several other BCG’s to compare the Sharps to and it is by far the best hands down. It cycles smoother, has less felt recoil, and just looks good. I will never buy another brand BCG. If your on the fence don’t hesitate it’s worth every penny.

  5. Dennis Kelly (verified owner)

    Great product would highly reccomend

  6. Kevin (verified owner)

    Just got my bolt carrier group today. she’s beautiful and cycles smoothers then sweet walls of glory.

  7. Geovanny Matias (verified owner)

    Love it love it

  8. Jackie Jones (verified owner)

    Always a great product.

  9. J. Rodriguez

    I’m ordering the nib next for my ar pistol in 300 bo I love my xpb bcg DLC in my rifle I couldn’t ask for any better its PERFECT great work sharps. These are the only bcgs in my life!!!

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