Menu
Your Cart

Xtreme Performance Bolt (XPB) Carrier Group in NiB-X Silver

Xtreme Performance Bolt (XPB) Carrier Group in NiB-X Silver
Xtreme Performance Bolt (XPB) Carrier Group in NiB-X Silver
Xtreme Performance Bolt (XPB) Carrier Group in NiB-X Silver
Xtreme Performance Bolt (XPB) Carrier Group in NiB-X Silver
Xtreme Performance Bolt (XPB) Carrier Group in NiB-X Silver
Xtreme Performance Bolt (XPB) Carrier Group in NiB-X Silver
Xtreme Performance Bolt (XPB) Carrier Group in NiB-X Silver
Xtreme Performance Bolt (XPB) Carrier Group in NiB-X Silver
Xtreme Performance Bolt (XPB) Carrier Group in NiB-X Silver
Xtreme Performance Bolt (XPB) Carrier Group in NiB-X Silver
Xtreme Performance Bolt (XPB) Carrier Group in NiB-X Silver
Xtreme Performance Bolt (XPB) Carrier Group in NiB-X Silver

Xtreme Performance Bolt (XPB) Carrier Group in NiB-X Silver

5.56 FULL AUTO BCG

    In stock Free shipping
    Same-day shipping and free shipping insurance included.
$229.99
Price in reward points: 7666
SKU: SRCXPBCG-NIBX
categories: AR15 Parts, All products, Bolt Carrier Groups (Full Auto)
MPI, HPT and Shot-Peened
Magnetic Particle Inspected, High Pressure Tested, and Shot Peened. Guaranteed to perform under pressure.
Limited Lifetime Warranty
Limited Lifetime Warrantyy

Description

The Sharps Xtreme Performance Bolt (XPB) Balanced 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. 


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


Why S7 Tool Steel?

S7 has excellent shock absorbing properties which provide superior impact resistance when being utilized in the construction of Sharps Bolt Carrier Groups. S7 demonstrates high strength and toughness as well as a resistance to softening at moderately high temperatures, i.e. operating temperatures not exceeding 1000°F. 


The properties we as shooters look for in an AR platform BCG, are hardness and wear resistance.  S7 provides such attributes when heat-treated properly. Sharps has found that the key benefits from S7 tool steel are higher tensile strength and toughness which translate to longevity of use, i.e., a higher number of cycles the bolt can handle before it fails.



  • 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.  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)



Limited Lifetime Warranty

If any SRC Bolt Carrier or Relia-Bolt™ is found to have manufacturer defects, SRC will repair or replace it at no charge. Manufacturer defects include out of spec parts and defective parts.  Although our BCG is Mil-Spec, there are so many variables, sometimes a little troubleshooting, or fine tuning of parts may be required for proper functionality.  Before a part is replaced or refunded, SRC reserves the right to inspect and test part(s) in question to determine if it is defective. Please keep in mind that altering the product renders the warranty void.

MPI, HPT and Shot-Peened
Magnetic Particle Inspected, High Pressure Tested, and Shot Peened. Guaranteed to perform under pressure.
Limited Lifetime Warranty
If any SRC Bolt Carrier or Relia-Bolt is found to have manufacturer defects, SRC will repair or replace it at no charge. 

Reviews

Add review

Bad Good
Your email address will not be published. Required fields are marked *

Join our newsletter and get $5 OFF

WHAT OUR CLIENTS HAVE TO SAY

I have always been a quarter-bore fan but I had been out of the shooting scene for a few years. I changed jobs and a coworker introduced me to the 25-45 Sharps. After seeing the how close the ballistics were to the 250 Savage (one of my favorite cartridges) it was pretty much a no brainer that I had to build one. Collecting parts on a budget can really try one's patience, but I finally got it finished the way I wanted it using not only a 20" SRC barrel, but a Balanced Bolt Carrier with Reliabolt as well. The barrel shoots great and the bolt is tough as nails.


January 26, 2021
I completed my first ever build in May. Since the BCG is supposed to be the heart of the rifle I wanted to do my research to see which direction I should go. After seeing so many positive reviews on YouTube, I decided on the SRC in FDE. I've put about 1000 rounds through this rifle and I haven't one malfunction or hiccup. I'm very impressed with the craftsmanship and quality that went into this bolt. I have some more builds planned and I'll be using the SRC BCG's on all of them.


August 27, 2019
One of the best bolt carrier groups you can buy. S7 tool steel and a really smooth NIB-X finish... I own a lot of premium BCGs and this is one of best I've tried. Definitely worth the money when you look at the extra machining that went into this, better quality steel, enhanced design and features and a great finish. Let's also not forget this is a small US based company that stands by their products. I'll be highly disappointed if Sharps ever goes out of business. With what little money I have to spare, I've already ordered more BCGs from SRC and I'll continue to support them as long as they're in business.


March 25, 2022
I have a light profile stainless 18" SRC barrel on my most recent build. It consistently shoots a little under MOA, and I used it to drop a 90 pound doe from 109 yards with a neck shot using factory 87 grain ammo. It was an instant kill and left a quarter size exit wound. My hunting buddies were very impressed.


February 11, 2022
This is my third Sharps DLC BCG. All are perfect and are used in two 5.56 and one 300Blk. Easy to clean and have never had ONE malfunction! Trust me the quality of these BCG is the best bar none. They do shoot softer and you can back off the buffer weights, I have backed off the adjustable gas block for one of the softest 5.56's around.


March 11, 2022
Exceptional BCG. The DLC coating is durable and cleans up easily. I've tried so many BCGs out there and these are my go-to because they are durable, reliable, and easy to clean up. I use them with 5.56 and .300BLK both suppressed and unsuppressed and they are good to go.


April 11, 2022
Even during all of the craziness in the world with this covid mess Sharps delivered an outstanding product in just a few days. I have reliabolts in all my rifles and a few of your extreme performance carriers. I have and will continue to trust your products with my life. Thank You.


September 16, 2020
Previously I was a huge fan of the brand that cost twice what this one does and has a mirror like finish. I needed a bolt carrier for my coyote gun and tried this. It is an amazing bcg and didn’t even have to change my gas block from the other brand. In my opinion this is the best tactical or hunting bcg.


January 27, 2022
After shooting around 150 rounds no cleaning and getting sub 1" groups all day long without any hick-ups , very impressive. And getting wows and complements on the feel and look of the weapon I am happy to say that this is a winner. The timing and feel when shooting was top notch. Thanks guys for the excellent service and help when purchasing.


July 13, 2020
Purchased a new upper without the BCG. MY intention was to give Sharps a try from scratch with the new upper. Was not disappointed, in fact was very happy that this BCG was as good as my research suggested. About 1000 rnds. So far. Ordered a new bolt for my other Ar15.


February 22, 2022
Great customer service. Seamless transaction. Was treated as if I was the most important customer they had. Great website, easy to navigate.


April 3, 2016
when you deal with the best,you get the best. thanks


December 16, 2018