WMD NiB-X Nickel Boron Bolt 5.56/.223/300BLK

Manufactured by WMD Guns
Manufactured by WMD Guns
5 Reviews

In Stock

Standard orders will ship out in 1 business day (M-F) if ordered by 3:30 pm CST. FFL orders will ship within 5 business days or less as long as we have the information for the transfer destination. NFA items will take longer to ship and are dependent upon ATF processing times.

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This complete AR-15 Bolt assembly comes pre-built with gas rings, extractor, and ejector. The bolt itself features WMD's proprietary NiB-X nickel boron coating which offers a high-lubricity for drastically reduced wear, maintenance, and oiling, and harder-than-chrome surface that will hold up to thousands of rounds of use. As an added benefit, it is also extremely easy to clean.
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Bolt FinishNickel Boron
Bolt MaterialCarpenter 158 Steel
BrandWMD Guns
Caliber Gauge5.56 NATO
High Pressure TestedHigh Pressure Tested
Magnetic Particle InspectMagnetic Particle Inspected
California Prop 65 warning

 WARNING: This product can expose you to chemicals, which are known to the State of California to cause Cancer and Reproductive Harm. For more information go to www.P65Warnings.ca.gov.

Ratings & Reviews

5 reviews

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head space


The bolt arrived on time and was what I needed to address a head space issue with a WMD barrel I had installed a Zero fail bolt but it what not gauge correctly with the WMD barrel it is now perfect.



This device is amazingly rugged. Even with brute force and pliers banging up against it on accident.Just be sure to clean up the firing pin hole. Also, clean up the hole for the cam pin too! There may be excess carbon from testing. If you got the NiB-X cam pin, it's a super tight tolerance fit.

Does its job

by -

No problems...does its job.

WMD Bolt

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I am using this to build a spare bcg, haven't fired it yet but it i

No issues as usual

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Never head a problem with any wmd products. Great products at great prices.